HARVARD UNIVERSITY Library of the Museum of Comparative Zoology MCZ LIBRAR\7 X Jl g J'J'^ 0 5 1992 HARVARg UMVERSrEy GREAT BASIN MURALIST VOLUME 52 NO 1 - MARCH 1992 BRIGHAM YOUNG UNIVERSITY GREAT BASIN NATURALIST Editor James R Barnes 290 MLBM BrighaiTi Young University Provo, Utali 84602 MichaklA howKHs Blandy ExperiuKMital F"anii University of N'irginia Box 175 Boyce, Virginia 22620 Pai'lC Marsh Center for Environmental Stndies Arizona State University Tempe, Arizona 85287 Associate Editors Jeanne C. Chambers USDA Forest Service Research 860 North 12th East Loiran, Utah 84322-8000 Brian A MAifRER Pepartnient of Zoology Brigham Yonng University Fro\o, Utah 84602 Jeffrey R. Johansen Department of Biology John Carroll University Cleveland, Ohio 441 18 JimmieR Parrish BIO-WEST, Inc. 1063 West 1400 North Logan, Utah 84321 Editorial Board. Richard W. Baumann, Chairman, Zoology; H. Duane Smith, Zoology; Clavton M. White, Zoology; Jerran T. Flinders, Botany and Range Science; William Hess, Botany and Range Science. All are at Brigham Yovmg University. Ex Officio Editorial Board members include Clayton S. Huber, Dean, College of Biological and Agricultural Sciences; Norman A. Darais, University Editor, University Publications; James R. Barnes, Editor, Great Basin Wituralist. The Great Basin Naturalist, founded in 19.39, is pvil)lished quarterly by Brigham Young Uni\ersity. Unpublished manuscripts that further our biological understanding of the Great Basin and surrounding areas in western North America are accepted for publication. Subscriptions. Annual subscriptions to the Great Basin Naturalist for 1991 are $25 for iiuiiN idual subscribers, $15 for student and emeritus subscriptions, and $40 for institutions (outside the United States, $30, $20, and $45, respectively). The price of single issues is $12. All back issues are in print and available for sale. All matters pertaining to subscriptions, back issues, or other business should be directed to the Editor, Great Basin Naturalist, 290 MLBM, Brigham Yoiuig University, Provo, UT 84602. Scholarly Exchanges. Libraries or other organizations interested in obtaining the Great Basin Naluralist through a continuing exchange of scholarly publications should contact the Exchange Librarian, Harold B. Lee Library, Brigham Young Ihiiversity, Provo, UT 84602. Editorial Production Staff JoAimc Abel Technical Editor C;ar<)l\ u Backman Assistant to the Edih)r Natalie Miles Production Assistant Copyriylit © 1^W2 l)y BriKliam Yoiini; Univt-rsitv Ofllci.il piililication dati; 22 Mav 1992 ISSN 0017-3614 .5-92 75055407 LIBRARY JUN 0 5 1992 The Great Basin Natiiralist Published at Prono. Utah, by Brigham Young Uni\ kusiit ISSN 00 17-36 14 " I r Volume 52 Margh 1992 No. 1 Great Ba.sin Natiiridi.st 52( 1 ). 1992. pp IN MEMORIAM— A. PERRY PLUMMER (1911-1991 TEACHER, NATURALIST, RANGE SCIENTIST E. Duiaiit McAitlm A. Pern' Pliininier died in tlie Gunnison \ixllev Ho.spitiil, Gunni.son, Utah, on October 3, 1991, after several years of iU heiiltli. His piissing deserves comment because he was a mixn who made a difference in natin'al re.source manage- ment luid research in the Intermountain area. He spent his professional career (1936-1979) with the Intermountain Research Station (INT, formerK' the Intermountain Forest iuid Range E.xperiment Station) of the Forest Senice, U.S. Department of Agriculture, at duh' stations in Utaii near Mil- ford and in Ogden, Ephraim, and Pion'o. Teagiier .\nd Mentor Perrv was a caring, effecti\e mentor and teacher. His assignment witli the Forest Service was research and research administration, which he did w(^ll; but his professional lo\ e was teaching, especialK' small groups and indixidu- als. His formal teaching was limited to a couple semesters at Brigham Young Universit)' (BYU) shortl\- after the 1975 establishment of INT's Shnib Sciences Laboratory on that campus. He e.stal)lished a wildland shrub biologv class that remains a part of the BYU curriculum, in addi- tion, he instnict(nl numerous workshops at the Great Basin Experimental liange (Ephraim Canvon) and conducted man\' field tours at out- planting, common garden, range rehabilitation, and other research sites throughout Utiili and the Intermountain area. Under these ci renin stance \s he was a master teacher whose points mad(" lasting impressions on whoever was there — agencx land manager, private landowner, public school teacher, Washington Office Forest Senice research administrator, politician, junior col- league, or uni\ ersit\ professor. Perry had a rare gift of integrating in his mind the potential vegetative states of degraded lands because he knew soil t\pes, compatible plant associations, plant adaptations, planting e(|uip- inent, and seedb(nl re(juir(Miients. Becau.se of this gift and his willingness to share it, he was often called on to consult those n'sponsible for rehabilitating degraded huids. Txpically. he would visit potential rehabilitation sites and folkm- up bv providing detailed w iitt(^n recom- mendations. He completed well over one hun- dred careful, thoughthil consultations lor tlie good of tlu^ laud, for those who manage it, and for its human and other occupants. He was a mentor to others wlio continue on in this tradi- tion: I think csnccialK of Steve \h)iisen of our ' Slinib Sciences Liihoniton,, IiiliriiioMTil.un Kesearcli Slalion. Kore.st Semce, U.S. Department of Agricnllure. Provo. Utah S4(t()6. Great Basin iNatuiullst [\ohinie laborator)' and Richard Stexens of the Utah Division Or W'ildHfe Resources (DWR) in Ephraini. I illustrate Pern's teaching st)le with a ])er- sonal example. In May 1972 I had been working for INT for four months when Perrv' took me on a field trip to the Brown's Park area of northeast- em Utah to exaluate the results of some earlier work (he took or sent me on monthly field trips those first two or three years). At one stop I saw a patch of green in the distance at a spring. I suspected monkey flowers {Miniiiltis sp. — the subject of m\- Ph.D. degree research a few years earlier) would be growing there. I hustled over and confirmed mv suspicion. Perry ambled up and said, 'It's nice to appreciate these monkey flowers the wa\ \ on do, but look back toward the tnick. What else (k) \on see? There aie lots of other plant species and plant communities between here and there. You can learn a lot by looking at the whole plant communit)." He laughed in his characteristic \\'a\', and we dis- cussed the \arious plant species present and their habitat requirements. A lasting lesson to me. it is similar to other Perrv teaching moments shared bv \n\ colleagues. Back(;rou\d, Education, Work Ethic:, and Honors Arthur Pern Plummer (Hg. I ) was bom on a farm in Daniel, Wasatcli Count\', Utah, on April 10, 1911. His mother died when he was young; he and his siblings had a resourceful, indepen- dent upbringing with their \\i(k)wer father. He was educated in the Wasatch Count\ public schools, at East High School in Salt Lake Cit)', and at the University' of UtiJi. Peny received a B.S. degree (1935) in botany from the U, began his INT career (1936), married Blanche Swin- dle of Monroe (1938), and completed his M.S. degree also in botany at the U (1939) in a busy h)ur \(*ars. He enjoyed his universitv' davs and called on that background and experience throughout his career. Notable among his pro- fessors were Kim Newby Walter Cottam, Ralph Chamberlain, Fayette Stephens, and Angus Woodburx. He and Doc" Cottam continu(>d a producti\ (■ interchange of ideas and shared field trips into the mid-]97()s. Perrv was a doer. He performed and worked hard. He didn't just a.sk his subordinates to get souK^thing done— he did it with them. As a new Ph.D., I didn't e.xpect to be on the bu.siness end of a hoe for .several hours a dav, but then 1 didn't expect mv boss to be in that situation either. He would show up anywhere a work crew was, reach' to help with \1gor and energv', and he expected anyone working to do the same. It wasn't uncommon for Perr)^ to show up at these sites at 11:30 a.m. or 4:30 p.m., seemingly unaware of the impending lunch hour or (quit- ting time. Perrv's record of accomplishment was noted by several organizations. In 1965 INT recog- nized him with a certificate of merit and a sub- stantial cash award for outstanding performance in wildlife habitat research and application f)f that research. Also in 1965 the Utah Wildlife Federation honored him as Consen'ationist of the Year. In 1973 the Utah Chapter of the Soil Consenation Societ}' of America gaxe him their Chapter Recognition Award. He received a USD A Superior Seivice Award in 1969 for implementing and luaking successful the coop- eratixe work between INT and DWR. Pern', a 1949 charter member of the Societx' for Raiiiie Management (SRM), was president of the Utah Section and received SRMs Outstanding Achievement Award (1974), the premier Fred- eric G. Renner Award (1976), and the Fellow Award (1977). He was president of the Utah Chapter of the Soil Consenation Societv during the early 197()s. Scientific Contributions In this section 1 comment not onl\ on Pern's direct contributions but also on work that he stimulated and inspired. Pern's contril)utions were not limited to those he personalK' made; but, like those of many great teachers, his achievements have been enhanced aiul expanded b\' those who came after and built upon the foundation he laid. ('onsidering Pern's later contriliutions to shmb biologx, it is of interest that his first pub- lication was on de\ eloping a techuicjue for prep- aration of microscopic sections of stems and roots of shrubs (Newby and Pluuuuer 1936). His master's degree thesis (1939), published in 1943, d{\ilt with germination and seedling development of range grasses. He continued his interest in seed germination, (jualitv, storage, and processing, and in seedling de\elopment, on a wick' range of plants throughout his career, and his successors have continued this work (Rudolf et al. 1974, Stein et al. 1974, Plummer 19921 In Mkmouiam — A. Pkkhy Pia \imkh Fig. 1. A. Pern,^ Pliimiiier in his office about 1975. and Jorgensen 1978, Stexeiis ct al. 1981, Meyer opment of procedures for revegetating degraded et al. 1989, Ste\ens and Me\er 1990. \Ie\er and lands, including plant materials and operational Monsen 1991). c(]uipnicnt infonnation and answers to liow. Pern's greatest contributions iuNolwd tlc\el- wlicn. \\li\. and where. He was priuian author Great Basin Natuiialist [Volume of three "how to" publications that have been broacllv accepted and applied (Plumnier et al. 1955, i96S, Plummer 1977). The 1968 publica- tion. Restoring Big Game Range in Utah, became a classic; it has been used extensively in the cKussroom and in the field and is now out ol print after several press runs. It is serving as the foundation of a new compendium for western wildland rehabilitation techniques (Monsen and Ste\ens, in press). Other publications of note for general and specific re\egetation applications include Phunmer et al. (1943), Stewart and Plummer (1947), Plummer and Fenlev (1950), Plummer (1959, 1970), Plunnner and Stapley (1960), Ste- vens et al. (1974), Hamer and Haq^er (1976), Giunta et al. (197Sa), McArthur et al. (1978b), Monsen and Phunmer (1978), Stevens et al. (1981), Mon.sen and Shaw (1983), Monsen and McArthur (1985), Da\is (1987), and Blauer et al. (in press). His earl\' rexegetation work led to a coopera- tive research and application xenture bet\veen INT and the Utiili Dixision of Wildlife Resouces (knowTi then as the Utali Department of Fish and Game) under Perry's direction. This effort was stinmlated bv big game winter range prob- lems brought on b> the [)artial urbanization of those ranges, large deer populations, and the heaxA' snowfalls of the late 1940s and earlx' 1950s. The program began in 1 954 at the behest of the directors of INT and DWR. It is the most extensive and longest running such arrange- ment in the countrx'. He and his colleagues from DWR produced 11 substautixe reports betxx^een 1956 and 1971 detailing their findings and rec- ommendations in revegetation science ( Plum- mer etal. 1956-1971).These reports, published by DWR, xvere sought out and used xx'idelx^ bx land management professionals. Perrx- had a particular interest in and impact on plant materials development including exploration, collection, evaluation, adaptation, culture, genetic xariation, hybridization, and breeding systems. In this area he read carefulK' and folloxx'etl the xxorks of Luther Burbank (wide and unusual hvbridizations, see Kraft and Kraft 1973), N. I. N'axilox- and E. V. Wulff (ori- gins and dexelopment of related plant groups, Wulff 1943, \'ax-ilov 1951 ), Jens Clausen, David Keck, and William Hicsev' (accessional or pop- ulational compari.sons in common gardens and reciprocal transplantations, Clausen et al. 1940), and G. L. Stebbins (natural hybridization and intraspecific variation, Stebbins 1950, 1959). He xvas particularly interested in applx- ing these concepts to xvestem shnib species, xx'hich had received little prior attention despite their obvious ecological importance. He spelled out his dream of a regional common garden testing scheme (LeGrande, Oregon; Boise, Idaho; Ephraim, Utah; and Reno, Nevada) in a 1972 document (Plummer 1972a). Although this dream was not fully implemented because of funding problems, several useful and interesting studies resulted — e.g.. Van Epps (1975), McArthur and Plummer (1978), McArthur et al. (1978c, 1979, 1981), Welch and McArthur (1979, 1981), Welch and Monsen (1981), McArthur and Welch (1982), Edgerton et al. (1983), Welch et al. ( 1983), Geist and Edgerton (1984), Hegerhorst et al. (1987). His specific interests in h\l)ridization, breed- ing systems, and genetic xariation and selection hav'e been addressed in a series of publications specific to certain shrub taxa (Plummer et al. 1966, Nord et al. 1969, Hanks et al. 1971, 1973, 1975, Plummer 1974b, Blauer et al. 1975, 1976, McArthur 1977, Stevens et al. 1977, Giunta et al. 1978b, McArthur et al. 1978a, 1978c, 1979. 1988, in press, Welch et al. 1981, 1987, 1991, McArthur and Freeman 1982, Davis 1983, Freeman et al. 1984, 1991, Davis and Welch 1985, Welch and McArthur 1986, Pendleton et al. 1988, Welch and Jacobsen 1988, Wagstaff and Welch 1991) and in more general terms (Drobnick and Plummer 1966, Plunnner 1972b, 1974a, Monsen 1975, Monsen and Christensen 1975, Ciu-lson and McArthur 1985, McArthur 1989). He had a keen eye for recognizing unusual and/or superior plant populations occurring nat- urally and in test plantings and in enhancing tliose materials for improved productivity and esthetics of degraded and badlv disturbed lands. Several of these collections have been given distinctive 'cultivar' or source identified names and released for commercial propagation and use by his associates since his retirement. These includ(^ "Appar" Lewis flax {Liniini pcrcnne). "Cedar" Palmer penstemon {Pcnstcnioii pal- nieri), 'Rincon' founving Sixltbush [Ati'iplrx canesrcii.s), "Hatch" xxinterfiit {Ccratoidcs laiidta), "Hobble Creek" mountain bigsagebnish (Aiiciiiisia tii(h'iit(ita ssj). vasci/ana), 'bnmignuit' forage kochia {Kochia prosinitit), "Lassen" antelope bitterbmsh (Piirsliia trident at a), "Ephraim" crested wheatgnuss {A^ropi/roii cristatnni), and "Paiute" orchardgrass {Dactijlis ^lonwrata) 19921 I\ MKMOHI AM — A. Pehhy Fiammkh 5 (McArtliur et A. 1984, Monsen and Ste\(^n.s 1985, Stevens and Monsen 1985, 1988a, 19881). Stevens et al. 1985, Shaw and Monsen 1986. Welch et al. 1986, McArthnr 1988). Othei .spe- cies and populations were not released but iiax'e had their usefulness documented and lia\(^ become axailable in the revegetation species repertoire. Perr\' Plunniier sened lor man\ \ears as the Forest Ser\ice technical representatix'e to the Western Regional Plant Introduction Couuiiit- tee (W-6). His plant materials expertise was put to use as a member of 1976 and 1977 plant collection and e.xplo ration teams in the So\iet Union (Dewey and Plummer 1980) and in 1980 as an on-site consultant in a New Zealand range rehabilitation program. He also stimulated interest in shnib disease and microbial and entomological relationships (Tiernan 1978, Nelson and Krebill 1981, Moore et al. 1982, Nelson 1983, Nelson and Tiernan 1983, Nelson and Schuttler 1984, Haws et al. 1988, Nelson and Lopez 1989). Aspects oi Pern's kne of plants can be high- lighted bv two that were named after him: (1) 'Appar' Lewis flax was the first of se\eral plant releases effected b\ INT, DWR, USD A Soil Conser\ ation Service, and sex'eral state agricul- tural experiment stations (the "App" in Appar is for his initials); and (2) Gravia brandegei ssp. phimnieri is a \\ide-lea\'ed tetraploid \ariet\' of spineless hopsage that Howard Stutz named in honor of its di.sco\erer (Stutz et al. 1987). These tvvo plants illustrate the poles of Perry's work: one is a show\' revegetation and horticultuial cultivar; the other a restricted edaphic endemic, new to science. Perr\ helped develop and refine equipment and techniques including anchor chaining, seed dribblers, scalpers, seed collection and process- ing, rangeland drills, and transplantation and interseeding equipment (Plummer et al. 1956- 1971. 1968). Lecacy Manx of FeriA "s 80+ |)ubHcations are listed in the Literature Cited section. .\si(k^ from these, I see the following components of his legacy: ( 1 ) with Blanche, a fine family of seven children, (2) an expanded scientific foundation that he and his disciples ha\e laid for wildland reclamation (see recent examples documented in the Liter- ature Cited section) and for the incipient dis- cipline oi shiub science, (3) hundreds of thou- sands ol acres of successfullv rehabilitated wildlands that retain sufficient plant diversitvto supj)ort a rich native fauna, and (4) a native wildland plant industrx' (.several seed companies in Sanpete Counts' alone owe their existence, at least in part, to Perrv and his team for back- ground information, collecting and processing techni(jues, and (k'velopment of a market for products). I will acklress onl\- item 2. Perrv beam his can^'r with the seeding, eval- nation, and development of range grasses (Plummer 1944, 1946, Plunnner and Stewart 1944, Plummer and Frischknecht 1952. Frischknecht and Plummer 1955). He was sinmltaneousK" involved in range management research (Rotli and Plummer 1942, Phunmer et al. 1943, Bleak and Phnnmer 1954) and sagebrusli control work (Pehmiec et al. 1944, 1954, 1965). Later, he managed the Great Basin E.xperimental Range in Ephraim Canyon (Keck 1972). When his assignment changed to restoration of wildlife habitat in 1954, he quickk' became conxertetl to the value of shnibs on wildlands. Perrv liked to recount his subsequent attempts to convert others to the value of shrubs, even the heretofore "weed " sagebnish, by recalling an anecdote. In the late 195()s he was with a crew on a vegetative rehabilitation project above a central Utah tovvni. The local Forest Service district ranger came bv' to see what thev were doing. Perr\' pointed out the v arious seeds in the seed mix — crested wheatgrass, orchard gniss, alfalfa, fourwing saltbush, Lewis flax, small bur- nett, etc. The ranger wanted to know what one particular small black seed was. When Pern- answered tliat it was sagebnish, the ranger took him to task for planting a weed. Perrv acknowl- edged that he, himself, had spent much of his career tning to rid western lands of that plant but pointed out that it was neeck'd for v\ikllife food and habitat. Thev were on a bciuli above a vallev. Below them was recentiv cleared land that had been choked with a thick stand of sagebnish. Pern- pointed out that there were good HMsons to do both: thin sagebrush stands and plant sagebrush. Pern had the vision to understand the useful- ness of all plants v\ithin acommunitv. He .sought to include the use of less common but important taxa, including buckwheat, globemallow, and smooth aster. He understood that plants sene main- important functions in addition to forage. He stronglv supported management and resto- Great Basin Naturalist [Volui ration efforts needed to improve disturbed sites. His standing, knowledge, and ahilit)' to work witli different people were extremely helpful to federal and state land management agencies as the\ attempted to balance livestock grazing pressure with earning capacity- of rangelands. He was particularh' interested in presenation and stud\- of natural plant communities. He worked to maintain the exclosure facilities of the Great Basin E\i)erimcntal Range and provided numerous plant vouchers for herbaria. His work with shnib management and values was important in garnering support for constmc- tion of the Shnib Scic^nces Laboratoiy. V. L. Haiper, retired Depuh (^hief for Research, Forest Service, sent me a letter in 1985: ... I wa.s dding ;i Rcsearcli In.spcction of the Iiiter- moiiiitaiii Station (about 1960) . . . One of the cen- ters Director Joe Peclianec and I \isited was the work on shrub rescarcli. After listenint^ to the Project Leader's {Perrs's) presentation and \'iewing some of the Held experiments, 1 turned to Joe and said "mavbe we ought to amend the Ten-year Reseaich Program to include a new laboratorv' at Provo . . . featuring shnib research including genetics, etc." Joe grinni'd broadk and said "I hoped von would see this need." He then produced a menx) outlining the justification for such a laborator\ to be located on the grounds of Brigham Young Uuixersitv. He further remarked, "I ha\'e outlined a speech which I can now cut sliort. eks b<4bre he died. He was at home between hospital stavs. It was pleasant to update him on lab activities. He talked about his friends and col- leagues who had gone on before and e.\press(>d the view that his time was near. Later, as I drove home, I reflected through mistv^ eves the good fortune I had of knowing and being mentored bv the man. .\hmv share this view. AcKNow i,Ki)(;\n:\Ts 1 thank Clyde Blaucr, Kim Ilaiper, Steve Mon.sen, Blanche Plummer. and Rich Stevens for u.seful comments on an earli(>r version of this memoriain. Literature Cited Bi.AUKH. A. C>"., E. D. McAhtiu H. R. Stevens, tmd S. D. Nelson In press. E\tJnation of roadside stabilization and beautification plantings in south centriJ Utah. US DA Forest Senice Research Paper. Intermountain Research Station, Ogden, Utah. Blai KH. A. C, A. P. Pllmmeh. E. D. McAirrm. h, R. Stem-ins. tuid B. C. Giln ta 1975. Characteristics and hybridization of important Intermounttun shrubs. L i^ose familv. USDA Forest Service Research Paper INT-169. Intermountain Forest and Range Experi- ment Station, Ogden, Utah. 36 pp. . 1976. Characteristics iuid h\iiridizati()n of impor- tant Intermountain shrubs. II. Chenopod famil\'. USDA Forest Sendee Research Paper INT-177. Inter- mountain Forest and Range Experiment Station. Ogden, Utah. 42 pp. Bleak, A. T, and A. P. Plimmkr 1954. Grazing crested wheatgrass bv sheep, [ournal of Range Management 7: 63-6s'. Cahlson. J. R., and E. D. McAUTiiUK, EDS. 1985. S\mpo- sium on range plant improvement. Pages 107-220 in Proceedings: selected papers presented at the 3Sth Annual Meeting of the Society for Range Manage- ment. Society for Range Management, Demer, Colo- rado. Claiskn. J., D. D. Keck and W. M. Hiesev 1940. Exper- imentiJ studies on the nature of species. I. Effect of \aried environments on western North Americiui plants. Cai'uegie Institution of W'ashington Publication 520. W'ashington. D.C. 452 pp. Da\ IS. ). N. 1983. Performance comparison among popula- tions of bitterbnish, cliffrose, and bitterbrush-cliffrose h\brid crosses on study sites throughout Utah. Pages 38-44 in A. R. Tiedemann and K. L. |ohn.son, compil- ers. Proceedings — research anil management of bitterbnish and cliffrose in western North .America. USDA Forest Senice General Technical Report INT- 152. Intermountain Forest and Range Experiment Sta- tion, Ogden, UtiJi. . 1987. SeecUingestablishmentliiologv and patterns of interspecific association among established seeded antl nonseeded species on a chained juniper-pinvon woodland in central Utah. Unpublished doctoral tlis- seitation, Brigham Young Unixersitv Pro\o, Utali. 80 pp. Dams J. N., and B. L. Welch 1985. Winter preference, nutritive \alue, and other range use characteristics of Kocliid prostnitd (L. ) Schrad. Great Basin Naturalist 45: 778-783. Di;w EV. D. R., and A. R Plimmeh 1980. New collections ol range plants from the Soviet Union. )ournal of Range Management 33: 89-94. Dkohnk K R., and A. P. Pllmmki! 1966. Progress in browse h\bridi/,ati()n in Utah. Proceedings, .Annual (Conference of Westi'ni State (iameand Fish ('onnnis- sioners 46; 20.3-211. EncEHTON. P. J, J. .M. Geist. and W. G. Wii.llvms 1983. Sourci's ol antelope bitterbnish in northeast Oregon. Pages 4.5-.54 in A. R. Tiedemann ami K. L. Johnson, compilers. Proceedings — rt'scarch and management of bitterbrush and cliffrose in western North America. USD.A Forest Senice (ieiieral Technical Report INT- 152. Intermountain Forest and Range Experiment Sta- tion, Ogden, Utali. 1992] l.\ Memohiam — A. Perry Piammer Freeman. D. C, E. D. McAhtiiih, and K. T. IIahi'kh 1984. The adaptive significance of .sexual lal)ilit\ in plants using Atiiplex caiwsccns a,s the principal exam- ple. Annals of the Missouri Botanicd Garden 7\: 265- 277. Freeman, D. ("., W. A. Ti rner, E. D. Mc.Artiu r and J, H. Graiia.m 199L Characterization of a narrow hybrid zone between two subspecies of big sagebrush (Artemisia trident ata: Asteraceae). American |ournal ofBotany78:805-.S15. Fri.sciiknecmt. N. C, and A. P. Pllmmer 1955. .\ com- piirison of seeded griisses under grazing and protection on a mount;iin brush bum. journal of Range Manage- ment 8: 170-175. Geist. J. M., and R J. Edc;kr ion 19.S4. Performance te.sts of fourwing saltbush tr;uisplants in eastern Oregon. Pages 244-2.50 in A. R. Tiedemann, E. D. McArthur, H. C. Stutz, R. Stevens, and K. L. Johnson, compilers. Proceedings — .svmposiimi on the biolog\' of Atriplex canescens luid related chenopods. USDA Forest Ser- vice Generiil Techniciil Report [NT-172. Internioun- tain Forest and Range Experiment Station, Ogden, Utah. GiUNTA. B. C., D. R. Christensen, and S. B. Monsen. 1978a. Interseeding shrubs in cheatgrass with a browse seeder-scalper Journal of Range Management 28: 398-402. GiUNTA. B. C., R. Stevens. K. R. J()rc;ensen. and A. P. Plummer 1978b. Antelope bitterbmsh — an impor- tant wildland shnib. Publication 78-12. Utah State Dixision of Wildlife Resources, Salt L;ike Citx. 48 pp. Hanks. D. L., J. R. Brunner, D. R. Christensen, and A. P. Pllmmer. 1971. Paper chromatography for determining palatabilitv differences in various strains of big sagebnish. USDA Forest Serxice Research Paper INT-101. Intermountain Forest and Range Experiment Station, Ogden, Utah. 9 pp. R-KNKS. D. L., E. D, McArthur, R. Stevens, and A. P Pl V M .M E R 1973. Chromatographic characteristics and phxlogenetic relationships of Artemisia, section Tridentatae. USDA Forest Serxice Research Paper INT-141. Intermountiiin Forest and Range Experi- ment Station, Ogden, Utah. 24 pp. Hanks. D. L., E. D. McAi^tiiur, A. P. Plummeh, B. C. GiUNTA, and A. C. Blauer 1975. Chromatographic recognition of some palatable and unp;ilatable subspe- cies of nibber rabbitbnish in and around Utah. Journal of Range Management 28: 144—148. Harner, R. F., and K. T. Harper 1976. The role of area, heterogeneitx; and favorabilitv in plant species diver- sitx' of pinvon-juniper ecosvstems, Ecologv' 57: 1254- 1263. Harper, \: L. 1985. March 17. 19S5. letter to K, 11 McArthur. on file at the Shrub Sciences 1 .aboraton, Pro\o, Utah. Hws, B. A., A. H. Roe. and D. L. Nelson 1988. Imlex to information on insects as.sociated with western wild- land shnibs. USDA Forest Serxice (General Tec-hnical Report INT-248. Inteniiountain Research StatioiL Ogden. Utah. 296 pp. Hegerhorst. D. F., D. J. Weber and E. D. M( An riiuR 1987. Resin and rubber content in Chn/sotluimnus. Southxvestem Naturalist 32: 475—182. Keck. W. M. 1972. Great Basin Station — sixty \ears of progress in range and watershed rese;irch. USD.\ Forest Serxice Research Paper lNT-118. Intermoun- tain Forest and R;uige Experiment Station. Ogden. Utah. 48 pp. Khai r K., and P, Kraet 1973. Secrets of the great plant wizard. Natural Histon- 82(8): 10-26. M( Arthur. E. D. 1977. Environmentallv induced changes of .sex expression in Atrij)lex canescens. Hereditx 38: 97-103. . 1988. New plant de\('lopment in range manage- ment. Pages 81-112 in P. T. Tueller, ed., Vegetation science applications for rangeland analysis and man- agement. Kluwer .Academic Publishers, Dordrecht Netherlands. 1989. Breeding SNstems in shrubs. Pages .341-361 in C M. McKell, ed.. The l)iolog\- ;uid utilization of shrubs. .Academic Press, Inc., San Diego, C^aliloniia. . 1990. Introduction: cheatgrass in\asion and shrub dieoff. Pages 1-2 in K. D. McArthur, E. M. Romnex, S. D. Smith, luid P. T Tueller, compilers. Proceed- ings— symposium on cheatgriLSS inxasion, shnib die- off and other aspects of shrub biologx and management, USDA Forest Serxice General Technical Report INT-276. Intermountain Research Statif)n. Ogden, Utah. McMthur, E. D., a. C. Blauer. A. P. Plumxier, and R. Stevens. 1979. Characteristics ;xnd hybridization of important Intermountain shnibs. III. Sunflower familx. USDA Forest Service Research Paper INT-220. Intermountain Forest and Range Experiment Station, Ogden, Utah, 82 pp. McArthur, E. D., and D. C. Free.man 1982. Sex expres- sion in Atriplex canescens: genetics and en\ironnient. Botanical Gazette 143: 476-482. McArthur, E. D., D. C. Freeman, L. S. Luckinbill. S. C. Sanderson. ;uid G. L. Noller. In press. Are trioecy and sexual labilit\- in Atriplex canescens genet- ically based? Evidence from clonal studies. Evolution. Mt:.\RTHUR. E. D., D. L. IUnks. A. P. Plummer. and A. C. Blauer 1978a. Contributions to the taxonomy of C'lin/sothamnns viscidiflonis ((^onipositae, Astereae) and other Chn/sofhamuus speties using paper chroma- tography. Joum;J of R;uige Management 31: 216-223. Mt:ARTiiUR. E. D., and A. P. Plummer. 1978. Biogeogra- phy and management of native western slirubs: a case study, section Tridentatae of Aiiemisia. Great Basin Naturalist Memoirs 2: 229-243. McArthur, E. D., A. P. Plummer. and J. N, D.wis 1978b. Rehabilitation of game ranges in the salt desert. Pages 23^50 in K. L. Johnson, ed., Wxoming shrublands: proceedings of the Seventh Annual Wyoming Shrub Eeologx' Workshop, Unixersitx- of Wyoming, Liiramie. McMthur, E. D., .a. P Plummer. G. A. Van Epps. D. C. Freeman, and K. R. Jorcensen. 1978c. Producing fbunving saltbush in seed orchards. Pages 406— 110 in D. N. Hvder, ed., Pr(K-eedings of the First Interna- tional Rangeland Congress, Societxfor Riuige Manage- ment, Denver, Colorado. \!< Arthur. E. D., C. L. Pope, and D. C. Freeman 1981. (-'hroinosome studies in subgenus Tridentatae of .\rie- misia: evidence for autopolvploidy. American Journal of Botany 68: 589-605. M( Arthur. E. D.,S. E. Stran.vthan. andG. L. .Noller 19(84. Rincon" foun\ing saltbush — proven for better forage and reclamation. Rangelands 6: 62-64. M< \RTiiUR. E. D., and B. L. Welch. 1982. Growth rate differences among big sagebnish (Artemisia tridentata) subspecies and accessions. Jounnil of Riuige Management 35: 396-401. 8 Great Basin Naturalist [Volume Mc.Ahtiiuk. E. D., B. L. Wklcii, and S. C. Sandehson ly.SS. Natnrd and iirtificial liybridization between l)ig sai^ebnisli (Artemisia tridcntata) subspecies. Journal of Heredity 79: 26S-276. McKl-.i.i.. C;. M. 19S9. The biolo120 g DW-m""-\T" ) or New Zealand streams (—40 g D\\'ni'"\T" ). Our data support the contention of othcis that production, rather than tlensitv or bioniass, is the most accurate^ and meaningful wax to assess die role of these organisms in lotic ecosystems. Kc'tj words: pwdnctiiity, benthos. sprin(^-streaiu.s. cold dcscii. fmictioitnl 'groups, trophic levels, Dijrtera. Tiiehopteni. Coleoptera. Epiieineroptera, Odonata. Plecoptera. Coniinunit\-le\el production of iiisect.s has been assessed in relatively few stream types, and of all niacroinxertebrates in exen fewer. Partic- ularh; little is known about secondan' produc- tion in arid region streams. The only studies of secondar\- production in arid region streams that we are aware of are those of Minshall et al. (1973) in Deep Creek, Idaho, in the cold desert proxince, and Fisher and Gra\- ( 1983) and lack- son and Fisher (1986) in S\'camore Creek, Ari- zona, in the hot desert region. Secondar\ production is the rate of animal tissue elaboration over time regardless of the fate (e.g., cannvorx; emergence) of that produc- tion (Benke and Wallace 1980). Estimating sec- ondary' production in a stream provides one assessment of the role of animals in the ecosvs- tem (Benke and Wallace 1980) as well as insight into ecoswstem dxnamics. Estimating onl\' den- -sity- and biomass. regardless of time, ma\' not accurately describe the role of organisms in the stream. For instance, the role of gathering-col- lector imertebrates was underestimated 1)\ bio- mass anaK'sis and o\erestimated 1)\ nunuMJcal analysis in a southeastern stream (Benke et al. 1984). Waters (1977) states that production is important to imderstanding ecoswstem d\ nam- ics because it is the means bv which cnergx is made a\ailable to higher trophic le\els. While most secondan production studies ha\ e focu.sed on one or a few species in a stream (Benke and Wallace 1980, Waters and Hokenstrom 1980. O'Hop et al. 1984). more recent studies have estimated secondan- pro- duction of the entire macrobenthic fauna (Kmeger and \\aters 1983, Benke et al. 1984. Smock et al. 1985, Ilumi and \\al lace 1987). Yet to be integrated into c()niiuuiiit\ -Icnx'I anal- \-.ses are the Inporheic fauna, proto/oa. and other microiuNfrtebrates. Thec()nnnunit\-le\el apjiroach proxides a mon^ integrated insight into the ecoIogN' of stream ecosvstenis. 11ie purpo.se of this study was to measure the secondarN' production of insects in three streams located in the cold desert physiographic pro\- ince of .southeiisteni Washington. We emphasize ^ Department ol Biolof^cul Sciences. Central Wa.shington Uni\ersit>\ Ellensbnri;, Wiusliini^on 9S926. "Present addres.s: U.S. Forest Service, l^>a\en\v()rtli Ranger District, Lea\en\v<)rtli, Wiusliinnlon 9SS26. En\ironniental Sciences Department. Pacific Nortliwesl Laliorator) , Ricliland. Washington 99.3.52. 11 12 Great Basin Naturalist [\ oiunie oz TaBI.K 1. Plivsical and chemical cliaracteristics of" stiicK ivaclus in Don^las Cn-i^k, SnKely Springs, and Rattle-snake Springs, July 19S5 to June 1986. Stream I^onglas C-'reek Snivelv Springs Rattlesnake Springs A\'erag(' widtli (m) 4.0 1.3 1.7 Axfragc de]itii 0.31 0.10 0.05 Axi'iagc discliargc invVs) 0.6 0.04 0.05 i)lSS()Kt'd()2 (nig/L) 9.6-14 8.6-12 8.2-10 T.Mil.K 2. Percent snitstiatnni t\pes in stnd\ reaches of Donglas Creek, Snively Springs, and Rattlesn;xke Springs, July 1985 to June 1986. Substratum type Stream Boulder (>256 nnn) Cobble ( 64-225 mm) Pebble (16-64 nnn) (Jraxel (2-16 nnn) Sand/silt {<2 mm) Douglas Creek SniveK Springs Rattlesnake Springs 21 7 0 29 20 1 24 25 7 16 11 11 10 37 81 (hat the estimates [)ul)li.shed here are, in sexeral cases, l)a.se(l on assnmptions that we have explained (see Methods). Given the choices to which we could devote the available resomx'es, we chose to prochice an estimate of total insect production in the.se spring-streams rather than detailed data on a few taxa. We hope futme studies will proxide data on growth, CPIs, etc., for all taxa in tlu^se spring-streams which we can then use to refine tlu^ initial estimates presented heri'. Study Sitks This shnih-.steppe region is characterized bv a climax conuiiunitx' consisting ofbig sage (Aiie- misia tridentata) and hluebunch wheatC), SniveK Springs (SS), and Rattlesnake Springs (RS) (Fig. 1 ). The axerage width, depth, discharge, and dissoKed oxygen concentration for each stud\ reach are shown in Table f , and the substratum composition is gi\en in Table 2. Figure 2 shows the daily and seasonal temperature rang(\s. Douglas Greek DG is a spring-fed stream located in Douglas Gouutx; \\'ashington. It is the largest ofthe three streams studied, the stream it.self draining an area of 530 km". Our studv sites were located in the upper reaches where flow is permanent and not affected bv irrigation withdrawal. Riparian vegetation is dominated bv water birch (Bctitld occidentalis) and peachleaf wallow {Salix anii/c^daloicles). Sni\el\' Springs SS is a small spring-stream located on the U.S. Department of Energy's Hanford Site, Wash- ington. It drains an area of approximately 40 km". The lower reaches ofthe spring-stream drv up during the summer, leaxing about 3.6 km of perennial flow (Gushing 1988). Riparian vege- tation is dominated bv cattails (TijpJui kit i folia) along the upper and lower reaches, and willow {Salix sp.) and wild rose (Rosa sp.) along the mid- reaches, where it flows through a canyon. Watercress {Nastuiiiimi officinale = Rorippa nastiii'titun-acjuatiniui) grows extensivelv within the s[)ring-stream. l^attlesnake Springs RS is a small spring-stream also located on the Hanford Site. It drains an area of 350 km" (Crushing et al. 1980). Portions of the lower reaches diA up during the summer, leaxing about 2.5 km of perennial flow. Mean annual total alkalinit\ (as C^aGO.^) is 127 ppm, and the spring-str(>am is subject to periodic severe spates in winter (Gushing and Wolf 1982, Gush- ing and (xaines 1989). Riparian vegetation is dominated b\- peachleaf willow and cattails. 19921 Insect Pkoduc:ti\ity in Spkinc;-Stkkams 13 Fig. 1. Stiulx ivachfs: A. noiujas Creek; H. Siiiwly Springs; C. Rattlesnake Springs 14 Great Basin Naturalist [\blunie 52 O 15- 0) I 10 CD Q. E I- 5 Y Snively Springs J I I I L J I L A S O N D 1985 F M A M J 1986 Fig. 2. ATimiiil water teiniXTdtiire regimes: Douglas Creek, Sniwly Springs, and Rattlesnake Springs, |nl\ 19S5 to June 1986. \\atfi-cTes,s is presentl)' the cloniiiiaiit in-.sti-eaiii Mkti K ) DS autotroph, altlioiigh periph\ton primary pro- chictioii exceeded that of watereres.s in 1969-70 We sampled seo;iiu^nts of eacli stream repre- (Ciishiiig and Wolf 1 984 ). senting the various hal)itats that were present. 1992] Insect Phodi (;ri\ irv in Simunc-S riiKAMs 15 One study reach was sampled in SS and one in RS, and three reaches were saniphnl in the larger DC. Samples were taken to calculate an average standing stock lor each stream to he used to calculate production estimates. The sampling scheme was not designed to allow intrastream comparisons ot production esti- mates hetween dilTerent hahitats, hut rather to pro\ide representatixe production estimates ol the entire stream. Samples were collected monthly from lul\ 1985 through June 19S6. We collected three samples during each visit. A Portable Inxerte- brate Box Sampler (PIBS) (0.1 m", mesh size 350 ^.m) was used in DC. A Surber sampler (0.09 m~, mesh size 350 |xm) was used in SS and RS because these spring-streams are too slial- low for a PIBS. Samples were taken to a depth of 10 cm and presened in 70% eth\l alcohol. Insects were separated from organic debris b\ sugar flotation (Anderson 1959) and sorted by taxa. Insects were identified to the lowest taxo- nomic level possible and counted, and bod\ length was measured to the nearest 1 mm using a microscope and ocular micrometer. The tro- phic status of each taxon was determined bv examining gut contents (Gaines et al. 1989) or b\- reference to Merritt and Cummins (1984). Biomass was determined as dn' weight (DW) for all size classes after dning at 60 C for 24 h and weighing to the nearest 0. 1 mg. The Size-Frequency (SF) method (Hviies and Coleman 1968, Hamilton 1969, Hynes 1980, Waters and Hokenstrom 1980) was used to (estimate secondare production of the most common taxa. An average SF distribution was determined from montliK' sample sets; these represented the sunixorship cune of an "axer- age cohort" (Hamilton 1969, Benke and Waide 1977); "zero" xalues xx'ere included xx'hen calcu- lating densities. Production xxas estimated bx calculating the loss between succ(\ssix-e size classes and then multiplving the loss bx the number of size classes using the etjuation gixen bx Hamilton ( 1969). Production estimates xx'cre rehned by multiplying by 365/CPI (Cohort Pro- duction Interval; Benke 1979). We fovmd that conducting groxxth studies lor all taxa present xxithin each of the streams xxas not practicable. To establish reasonable (\sti- mates of larxal dexelopment times and CPIs, xxe followed the example of Benke et al. (1984), xvho u.sed axailable life-histon- data and field data to estimate CPIs. We used three major sources of information to estimate CPIs for each taxon in our study streams. First, xve surxeyed [\\r ax ailable life-histor)' data gathered from lit- erature reviexx's and extrapolated the results to applx' to our situations. Second, xxe made field obsen'ations to dctcruiiue presence/absence of taxa and collected size-lre(juencv information for each taxon to estimate larval development times and (>PIs. Lastlx; xve conducted in situ groxxth studies for Bactis sp., Clicuiiuifopsi/che sp., and Sintulijini s[). to alloxx fuiilici- refine- ment of our CPI estimates. These groxxth stud- ies inxolxed placing insects xxithin groxx'th chambers in RS. Chambers xx'ere constructed xxitli mesh netting on each end to alloxv water and food material to pass through. Measure- ments xx'cre taken and dexelopment times recorded to estimate CPIs. Using the combina- tion of all these data sources, we feel confident that our CPI estimates are reasonable apj'jroxi- mations. Production/Biomass (P/B) ratios (Waters 1977) xxere used to estimate secondan produc- tion for less-abundant taxa. These P/B ratios xx'ere either ta.x()n-specific xalues derixed from the study streams or an assumed cohort P/B xalue of 5 (Waters 1977, Benke et al. 1984). These taxa xx'ere not present in sufficient num- bers to proxide an accurate SF distribution cune that is necessan to compute SF produc- tion estimates. RKS LILTS Production calculations for DC, SS, and RS are gixen in Tables 3, 4, and 5. respcH'tixclx-. The folloxving text describes some ot the assmnj)- tions xve u.sed in our calculations, data support- ing the.se assumptions, and other information relexant to the production calculations. .All pro- duction estimates, unless noted otheivxise, are gixen in units ol iiig DW-m" xr . Douglas ( ,'rcek Fpih:MEROFT1:u.\. — Maxilies txpically exhibit xxidelx- xaried laival dexelopment times (Clif- ford i982). Clifford (1982) examined life-cycle data of 85 species of Heptageniidae and found that >909f had at least one unixoltine cycle. Field data for Baetis sp. in DC proxided little clarification of the CPI. Based upon field data oi' Baetis sp. from RS and SS, and agroxvth study in RS, xx'e estimated a CPI of 60 d. Similar temperature regimes in DC and RS support this 16 (;heat Basin Natuhalist [Volume 52 TaHLK .3. Annual production ofinsects in Douglas Creek, JuK 19S5 to June UlSfi. (.'alculation 365/C:Pr' method X/in" B Annual production SE CV (mcrDW/m-) SE C\' (lus; DW/nr Ephemcroptera Bart is sp. (jjc. D)'' F(ir(ilq)toplilehi(i sp. (gc, D) U'ucwctita sp. (g. ID Tricon/tluxlcs sp. {gc, D) TOT.M. Odonata An^id tibialis (,p, (;) Plecoptera Isopcrlii sp. (p, C') IVichoptcra lli/dropsi/cltc sp. (fc, D) Chatmatopsrjchc sp. (fc, D) LcucDtriclua pictipcs (g, H) TOT.M, Coleoptera OpfiosciTus sp. (g, II) Diplera Cliiniiioinus sp. (gc, D) Siinitliuiu sp. (fc, D) ParautcthiHiH'inns sp. (gc, D, Chdctodadius sp. (gc, D) Hcloiiclla sp. (gc, D) Tipulidae (s, D) Pluiciiospcctrd sp. (g, ID Poh/fK'diluiii sp. (s, II) Tahanidae (p, C) Tlii('itcnuimiii)ii/ia sp. (p, C) Brillia flaiifrotis (s, D) Enipididae (p, (>) ToT.M. Gk.wo Total 6° r 9° r 1.5° 12° 15° 1.5'^^ 1.5'^ r 9° l.S° 1° 15° 1.5° 15" .SF' SF SF PBd PB SF SF SF SF SF PB PB SF SF SF PB PB SF PB PB PB PB 2416 0.41 92.4 225 0.35 7S.5 IfiO 0.47 104.0 (i 0.80 1.59.2 2S()7 .30 0.46 103.9 77 0.5S 129.4 445 1.56 95 696 753 41 196 115 141 37 60 1451 9.3S3 0.57 0.53 0.63 127.1 118.3 139.7 0.71 0.75 0.44 0.57 ()..52 0.37 0.07 0.69 0.48 0.81 0.25 0.22 1.52.3 168.6 98.0 127.8 116.4 82.5 15.5 1.54.5 106.6 180.5 .55.0 50.0 263.7 48.1 51.4 1.7 364.9 8.9 42.8 413.5 84.1 7.7 505.3 4.322 0.37 83.5 606.7 60.7 31.2 10.4 3.5 4.5 82.1 4.9 2.2 27.8 0.9 0.9 0.1 229.2 17.57.8 0.41 91.9 0.38 85.4 0.51 104.0 0.67 151.0 0.49 1 10.3 ()..58 113.9 0.65 145.8 0.60 1.35.0 0.68 153.2 0..36 80.0 0.69 0.72 0.46 0.66 ()..54 0.48 0.07 0.78 0.48 0.83 0.26 0.18 1.53.8 1.36.1 101.9 129.4 1 16.5 103.1 15.0 129.1 107.5 185.4 .57.4 40.0 S320 249 238 884 44 183 1700 818 32 2550 2160 4920 1680 875 426 423 411 221 161 1.30 75 68 8 9358 2,3219 Annual P/B 31.5 5.2 4.6 45.0e 5.0'' 4.3 4.1 9.7 4.2 3.6 81. If 54.0' 84.1 121.7 94.0 5.0" 45.0'' 73.1 S.O'' 83.6* 75.0'' 75.0" 'Sdurcc of (.-pi used; ° = iirce.s \vf re not iivailal)If) 's = shredder. i;c = j;allifriiii;-collector; Ic = lilli'nnij-collrctc 'SK = ])r(xliicli()ii Ciilc:ilalcd 1>\ llic Si/r-Krci|iiciic\ iiietliod ■'I'B = prodiKlion calculated 1» an ,i.sMiiii<-d IVH n.lio '.•VssiuiiedLoliort P/Holo. '.VsMiined .iniiu.il I'/H is tlie same as dcnved In SF l,,i diis 1, d.ila.nidSKdlstnlniti.i.is: .. = liti-r.itiiiv. = Sra/er/scnii.cT; p = prrdatni' II = lierln 111 ciiii-r.rtlie ntluT si ud\ streams lusi-dupc.iiCPl t, ic; D = detntiNore; iilar eited insects (used when e.stiiiiatc. Paralcptophlchia .sp. i.s geiu'ralK iiiii- voltine, haxiug either suninier or winter cycles (Ciiriord 1982). In DC, however, sea.sonal cycles coukl not be distinguished. Pairileptopltlchia were present in DC throughout the studv vear, and we assumed a CPl of 1 yr. Because of low numbers of" Tricon/tluxle.s sp., field data pro- vided little indication of their CPI. McCullough et al. (1979) reported a 34-d laival development time for T. iiiiiiittn.s grown in the field at ISC; therefore, we estimated a CPI of 40 d for Triconjthodcs sp. because of lower stream tem- peratures in DC. OUONATA. — The dam,selfly AroUi tibialis is inii\-oltine. Pi .Fcx )PTE RA.— A CPI estimate for hoperla .sp. could not be made from Held data. Sexeral stud- ies (Macka\ 1969, Haiper 1973, Barton 1980) o( Isoperhi sp. showed seasonal variation in growth rate, but generally their development time was about 1 yr. Therefore, we assumed a CPI of 1 \t. TlUCHOPTERA. — Lcticotrichio pictipcs was uni\()ltin{\ and as SF distributions and field data indicated, the lanae oxei-wintered as late instars and emerged in spring. This obsenation is sup- ported by studi(\s on L. pictipcs in Owl Creek, Montana (McAuliffe 1982). COLEOi'TERA. — An accurate CPI estimate for the riffle beetle Optiosctxiis sp. was difficult to estimate because few data are axailabie con- cerning their development times. W'e tlius assumed a CPI of 1 yr. 19921 Insect PHoniuTiN ity i\ Si'hi\(;-Sthkams 17 Tahi.I-: 4. Ainnial protliiftioii ol insects lidiii Siii\cl\ Spriiuj;s. |uK 19S5 to |mic 19.S(i. .\iiiiual ( 'alciilatioi 1 B procliictioii .\iiiiual .m5/c;pr' inctliiKl Wiii- SF (:\ ingDW/iii- ) SF C\ (mg DWVin") P/B Ephemcioptera B(icti.ss\\ (jic D)'' f-.= SFc I.ISS 0.fi2 104,7 1 S5.4 0.55 96.3 7010 37.8 F(iral('j)t(>])lil('hin sp. (gc, D) V SF 5-1 0.27 47.5 15.5 0.28 48.2 67 4.3 TOIAI, 1442 200.9 7077 OHonata .\r<^i/i lihialis (p, C) r PB'' 22 0.(il 1 06.6 27.8 0.(iS 118.6 139 5.0'' Trichoplera ('liciiiiiiitojisiichc sp. (fe. D) 2+-0 SF 433 0.41 83.0 200.9 0.51 86.9 1300 6.5 Dipltia SiinulitiDi sp. (fc, D) 12+,° SF 27fi 0.70 121.3 34.3 0.82 142.6 1880 54. S Cliironoiniis sp. (gc, D) 15° SF 412 0.54 93.2 17.1 0.58 99.8 1390 81.1 Tipulidac (s. D) 1° I'B 25 0.60 103.8 219.2 0.50 87.4 1100 5.0e Hi'lciiiclla sp. {gc, D) 15° SF 381 0.40 69.2 9.2 0.37 64.7 .550 60.3 PoUjpcdihini sp. (s, H) 18° SF 123 0.56 96.2 3.2 0.52 89.1 220 68.6 Cluictochidiiis sp. (gc, D) 15° SF 92 0.63 108.3 2.7 0.69 120.2 210 77.8 DLxicIae (gc, D) 15" PB 21 ()..55 95.9 1.3 0.(i5 1 1 1 .5 98 75.0*' Thieii('iiwintii)u/i(i sp. (p, C) 15° PB 18 0.42 72.3 1.1 o..3;5 57.. 3 92 S3.6'' Talianidae (p, C) 1° PB 52 0.47 81.5 10.5 0.50 86.4 53 s.o'- Enipiilitlae (p, C) 15 PB 4 0.15 26.6 0.6 0.12 32.1 45 75.0'^ T( ) I'A! . 1404 299.2 5638 Chand Total 3301 728.8 14,154 .)t(;l>Illsecl: Ml, ■'s other sources uere not a\'ailalile I- 's = slireclder; gc = gathering-collector; fc = niteriiig-collector: [^ - '.SF = production calculated In the Size-Frequenc\' method ' I'B = ])rothiction calculated In an ;i5sunied 1V15 ratio ' Assunu'd cohort IVB o(5. Assumed annual IVB is tlie same as ileri\ed In ,SF tor this taxon ii L.i.i IS|-,l,sl,,l.„l,.,ns , /scraper: II = lierl.i i)t the other stud\str<-ai n- - r Ims..I m|...ii( I'I r..r detriti\(ire; (^ = camix'ore. DiPTFB.X. — Simiiliiim sp. were not present in sufficient numbers in DC to calculate an SF production (\stiinate. The P/B ratio was calcu- lated 1)\ axeratfing the P/B ratios obtained for Siinuliiiiit sp. in SS and RS b\- the SF method. Accurate CPI estimates for (^hironomidae could not be obtiiined from field obsenations or SF distribution. Therefore, we derived CPI esti- mates, as did Benke et al. (1984), and u.sed growth data from Macke\ (1977). Macke\ (1977) reported lanal development times of 21 d for Chiroiioiniis sp., 13 d for Poli/pcdihim com idiiin. and 36 d lor Phaenospectra jlavipcs at 15 (;. CPIs were compensated for slightK lowx^r a\'era(2;e temperatures in D(> (13 (^) and eii\irouuienta] stress (e.g., food axailabilitA', competition, etc.). These P/B ratios seem high but are comparable to other data \vher(> short CPIs were used to estimate P/B ratios (Benke et al. 1984, Jackson and Fisher 1986). Tabanidae and Tipulidae were assumed to bc^ unixoltine with a dexelopment time of 1 \r (Knieger and Cook 1984). This is consistent with the estimate of a 1-yr development time for Tahaiiiis dorsifcr in S\camore Creek, Arizona ((wax 1981). Empididae grew to a maximum .size similar to nuun of the midges; therefore, a CPI of 25 d was Snix'cK Springs EPIIFMFHOITFHA. — (irax' (1981) reported a lanal dexclopnu^ut time of 20 d lor Bactis (jiiiUch in Sxcamore Creek, Arizona. Because of knxer stream temperatures, howexer, Bactis sp. dex(^lope(l more sloxvlx in all streams in this studx'. We assumedaCTT of 6()d. ParaJcpto))lilc- hia sp. xxas present oulx' during the sununer; thus, xx'e used oulx summer data to ciilculate production because annual P xxas essentially e(jual to sinnmer P. OdonaPA. — Ar<^ia tibkilis was not present in suffici(>nt numbers to make an SF production estimate. TUK.llOPTFHA. — Field data and SF data indi- cated a bixoltine life ex cle and a CPI of 6 mo for Chen mat opsijche .sp., the only caddisflx in SS. Dli'TFIVV. — Becker (1973) reported a lanal dex clopment time of 13 d for .S. vittatum grown in the laboratorx' at 17 C. A 30-d CPI xx'as esti- mated considering loxx-er stream temperatures 18 Great Basin Naturalist [Volume 52 Tahi.f: 5. AnniiiJ prochiction of insects from Rattlesnake Springs, July 19S5 to June 1986. Calculation 365/CPr' method N/m B SE (:\' (mgDW/m-) SE Annual production CV (maDW/m2) Ephemeroptera Bactis sp. (gc. D)' TricDnjtluxIcs sp. (gc, D) TOIAI. Odonata .Ari^fV/ tibial is {p, C) Trichoptera Clicitmatopsijclw sp. (fc, D) Parapsijclie sp. (fc, D) LimncphiUis sp. (s, D) ToiAl. Cole<»ptera Hi/ddticiis sp. (p, C) IKdropliilidae (p, C) ToTM, Diptera Siiniiliitin sp. (fc, D) Chin)ii(»nus sp. (gc, D) Helcnielld sp. (gc, D) Tlii('iicm(tiiiii)nt/i(i sp. (p, (J) Tahauidae (p, C.) Misc. C'hironomidae (gc, D) Polijpcdiliim sp. (s, II) Cliactorladiii.s sp. (gc, D) Empididae (p, C) TipuIidae(s,D) Di,\idae(gc. D) TOTAI. Grand ToiAi. Annual P/B go,.,o SEc 1336 0.61 107.2 47.3 0.58 104.0 2540 53.8 9" BB'' 1 1.337 0.05 8.3 0.3 47.6 0.07 12.2 14 2554 45.0'' r BB 67 0.72 124.1 74.3 0.78 134.9 372 5.0'' 20. + .0 SF 140 0.69 118.9 48.6 0.78 134.5 486 10.0 1- PB 10 0.24 41.7 26.8 0.25 43.4 134 5.0" 1 PB 52 202 0.45 76.9 22.0 97.4 0.38 66.3 115 735 5.0'' r PB 4 0.50 87.4 1.2 ()..35 60.1 6 5.0'' r PB 1 5 0.27 47.6 0.3 0.25 43.1 2 S 5.0" 12°"° SF 1777 0.73 125.8 212.3 0.73 127.5 11,180 52.6 15° SF 192 0.50 87.3 7.0 0.58 IOCS 489 69.9 15° SF 352 0.51 89.0 5.4 0.51 88. 4 480 88.9 15° SF 114 0.55 94.9 3.3 0.55 95.2 279 83.6 1° PB 34 0.51 85.6 15.9 0.64 111.0 80 5.()e 15° PB IS 0.29 50.1 0.8 0.38 66.3 60 75.0" 1S° PB 13 0.62 108.2 0.6 0.46 78.9 41 68.6* 15° SF 59 0.73 126.4 0.4 0.56 97.7 30 75.0 15" PB 8 0.39 68.3 0.4 0.23 39.8 30 75.0" 1° PB 3 0.21 35.9 2.0 0.26 44.3 10 5.0" 15- PB 2 2572 4183 0.28 64.7 0.1 248.2 469.0 0.29 50.0 8 12,687 16,356 75.0" mlli Nludiis : + = l!.-|(l , ;lat.iamlSF,lisliil .uho„s:„ = lilrralniv - = :lMM..l„pn 11 CI'I lors innUutcanivt ■1^ "l-i- = tilti-ring-o .>ll<-ct<,r, n = gruzer/scraper; p 1 = predatiir ■:II =lK-rl,lv„ „v: D = (let ntnort-: C; = carnivore. 'Source of CI'I used: " = derived troiii other sources were not availalile). s = shredder: gc = gathering-collector; 'SF = prcxliiction calculated l)y the Size-Fretjuencv method ' PB = production calculated by an assumed P/B ratio 'Assumed cohort P/B of 5. Assumed annual P/B is the same a.s derived by SK for this taxon in oni- ol the otiii'r study streams and en\'iron mental stress. CPIs of C^hironom- idae in SS were estimated as thev were in DC. We iLsed Grays (1981) estimateOf a 1-yr CPI and nnivoltinism for Tabanidae and Tipulidae. Dixidae and Empididae reached ma.xinnmi sizes similar to manv of the midges, and a (>PI of 25 d was assumed. Rattlesnake Springs Ephemeroptera.— We isolated several Bncti.s sp. lar\ae in growth chambers in RS to estimate lanal development time. These data and field data indicated a CPI of 60 d. Tricon/tlKulcs sp. were not present in sufficient numbers for an SF production estimate. OiX)\ATA.— Field data for Arg/V/ tibialis indi- cated a CPI of 1 vr. Trichoptera.— We isolated several Chcumafo- psijclw sp. lan'ae in growth chambers in RS to estimate lanal development time. These data indicated a bivoltine life cvcle and a CPI of 6 mo. Because of low densities, field data ga\e no indication of the CPIs of LiinncpJiihis sp. or Farapsijchc sp. COI.EOPTERA. — Field data pnnided little indication of the (]PIs of beetles because of low numbers. Diptera. — Several Siinulimit sp. lanae were isolated in growth chambers in RS to estimate lanal development time. As in SS, we used (irays (1981) estimate of a 1-vr CPI and uni- Noltinism lor Tabanidae ami Tipulidae. Dixidae and I'jupididac^ grew to maximum sizes similar to main ol the midges, and C>PIs of 25 d were assumed. 19921 InsectPiu)i:)U(:ti\ rn i\ Sfhixc-Sti^kams 19 TvHl,! (i. \iiiiual production (P. nuj; l)\\ -in x r- 1 ' and ])iit<-nt production ol insect tnnctional <4ronps in Douglas C.Vcek, Sni\rl\ Springs, and Rattlesnake Springs, )nl\ 1SIS5 to |nnc 19S(i. Functional ''roup Douglas (Jrcek Sni\fl\ Springs 7f Rattlesnake Springs (;r;i/.i'r/scraper Collector (Jatlierer Filterer (Totd) Slui'dder I'lcdator (;i{\\i)i()r\i. 2(i51 11.4 0.0 15.2S2 65. ,S 9332 65.9 .3621 22.2 4198 18.1 3177 22.5 11.800 72.1 (19,4.S0) (83.9) (12.509) (88.4) (15,421) (94.3) 639 2.S 1316 9.3 166 1.0 449 1.9 329 2.3 769 4.7 23,219 100.0 14.1.54 lOO.O 16..356 1(K).0 TaHI I 7. Annual production ( F, nig DW'in "-nt-D and percent production ol insect trophic le\els in Douglas C^reek. Sni\c'K .Springs, anil Rattlesntiki' Springs. |uK 1985 to |une 1986. Trophic IcN-el Douiilas CJreek 'Tf SnixeK Sprinjj <-/< Rattlesnake Springs ^f iirrliixorr Detritixore ( 'aniix'ore ToTvl. 2SI2 121 19.967 Sfi.O 440 1 .9 2:>.2I9 1 ()().(> 220 1.6 13.605 96.1 .329 2.3 14.154 100, 0 4 1 0.3 15.546 95.0 769 4.7 16.356 100. 0 Functional (yi-oiip Production Production In collectors Wius greatest of all func- tional groups in all stud\ streams. ( Collector pro- duction was highest in DC, 19.5 gin'~\T' , accoiuiting for 83.9% of the total annual produc- tion of insects. In SS and RS. collector production was 12.5 gaud 15.4 g, representing 88.4 and 94.3'/f ot the total aruiual production, re.spectixeK . The annual pioduction of ;i]l ftiuctional groups in each stud\ stream is sliowu in Table 6. IVopliic Ije\('l Production Heihixores and detritixores are both second- an producers at the same trophic le\el; carui- xores are teitiarx producers. Fortliis discussion, we address them .separateK. Detritixore pro- duction was greatest of all trophic lexels in each stuck stream. In DC, detiitixore production was about 20.0 g in'~\T' , accoimting lor 86.()9( of the total annual insect production. In SS andHS, detritixore production xxas 13.6 g and 15.5 g, rejn-esentiug9rs.l and 95. 09^ of"th(^ total amuial insect production. Herbixores contributed 12.]'^^ ol the productixitx' in DC", but no other tropliic lexel in anx of the three streams x\as an important contributor to secondaiA j)roductiou. The annual production of all trophic lexcls in each stream is i£ixen in Table 7. Discussion Interstream (Comparisons DC x\as clearlx the most productixe of the three streams studied (Table 6), and this is prob- ablx' related to the xaiietx' of substratum (Tal)le 2) and resulting increase in microhabitat diver- sit)'. Minshall (1984) thoroughlx rexiexxed the importance of substratum heterogeneitx' and its influence on insect abundance and distiibution. SS and HS xxere similar in size and had similar total productixit\- estimates (Table 6), although im[)ortant differences existed among the biotic coniponeMits. In t(Mnis of hmctional group productixitx', col- lectors dominated in each of the streams. Gath- erers xxere more important in DC and SS, and lilterers in HS. The greater filterer/gatherer ratio in US is probablx related to the shifting nature of the sandx' substratum (Table 2) and resulting absence of areas lor detritus to collect and be hancsted. The filtering sinuiliids occurred on the abmidant xxatercress plants. The scarcitx of solid snbstratimi for periphxton dext'lopment in HS also explains the absence of grazers in this stream. Htnxexer, substratum composition does not explain a lack of grazers in SS, xx'here solid substratum is present (Table 2). 20 Ghkat Basin Naturalist [Voluni In SS, tlie dense riparian canopy almost coni- pleteK' sliaded and obscured the stream. This proliahK pre\ented the development ol a sub- stantial periplutic food base (or grazers. In DC, which had both solid snbstratnm and unshaded stream bottom, a significant grazer commnnitx was present (Table 6). Comparing die prodnctixit) of taxa common to all three streams shows some differences that are difficult to (^xplain (Table 8). For example, Si)miliitiit sp. production was similar in DC and SS, but was an order of magnitude greater in RS. This nia\ indicate a richer source ol suspended food in RS; howexer, comparatix (^ measure- ments of this resource were not made, (wishing and Wolf (1982) report a \alue of L513 Kcal !n'~\r" of suspended POM in RS, but comparable data are not available for DC and SS. This value is much less than diat reported In iMinshall ( 1978) for Deep Creek, a small, cold desert stream in .southeastern Idaho. Since SiimtUum sp. production far exceeded that of auN- other iu.sect in RS (Table 5), competitive exclusion (Hemphill and C'ooper 1983) max make it more sncc("sshil in competing for the limited attachment sites. CJ}eiinuttoj)si/clie sp. and Paraj)si/c)i(' sp., two filtering Triclioptera in RS, had a combined production of 620 mg as compared xxitli Sintiiliinii sp. production of > 1 1,000 mg. This is a 20-foId difference for organisms of the same functional group. Except for Siinnliiun sp., dipteran production xvas high- est in D(" for Chiroiioiims sp. and Tabanidae, xvhile in SS. production oi' PoltfpediliDit sp. and Tipnlidae xxas highest. Tipniidae j)rodnction increased bx' an order of magnitude from RS to DC to SS. This max be relatcnl to the relatively high amounts of particulate organic matter (POM) found in the study .section of SS (Cush- iug 1988). Production of Bactis sp. is three to four times loxx-er in RS than in the other txxo streams (Table 8). A likely explanation lor some of the difler- ences shoxxii in Table 8 is the xxinter spates lliat occur in RS, but not in SS or DC. These spates, described by Cushing and (;aines (1989), .scour die entire streambed, flushing out accumulated POM and much of the fauna. They occur about exerx three xears and act as a "reset" mecha- nism. Because they occur in xxinter xx'hen there are no oxipositing adults, and because they scour and eliminate sources for both upstream migration and doxxTistream drift, thex- must T.ARi.K (S. (Comparative annual production (mg DWin^-yr- I ) of taxa common to Douglas Creek, Sni\'el\- Springs, and Hattlesnake Springs, |ul\ UiS5 to |une ]9Sfi. Douglas Sni\'el\ Rattlesnake TiLxon Creek Springs Springs Ephemeroptera Bdclis sp. 8317 7012 2542 Odonatii .4rg(V/ tibialis 44 1.39 372 Trichoptera Cliniiiisi/clu- sp. SIS 1298 486 Diptera Siiiiii/iinii sp. IfiSO 1879 11.175 Cltinnioiiins sp. 4920 1386 489 Poh/jx'dihiin sp. 161 220 41 Tabanidae 130 .53 80 Tipulidae 411 1096 10 severely limit the potential productixitx of RS. It is notable that the dominant secondarx* pro- ducers in RS are the black flies, organisms that are found in abundance soon after discharge diminishes (Cushing and Cxaines 1989). Intrastream Comparisons DouCiLAS Creek. — Secondan production in DC xx'as spread over a wider varietv of fimctional groups (Table 6) and trophic lex'els (Table 7), exen though it xx'as dominated bx' detritus-feed- ing collector-gatherers. Cliirononiiis sp. and Baeth sp. xx'ere the dominant secondan produc- ers in the stream. Snix'ELY Sprincs. — In SS, about 50% of the secondan- production xvas due to Baetis sp., a tletritus-feeding collector-gatherer; and, as mentioned aboxe, the grazing component xx'as absent. Total dipteran production xxas of the same order of magnitude as that for Bactis sp. but xx'as spread out among several organisms, notablx Siinulitdii sp., Cliiro)wmtis sp., and Tipulidae (Table 4). RaTTEESXAKK SPRIXCS. — Secondan pro- duction in RS xxas less dixerse than in the otlnM- studx' streams, xxith oxer 68% of the production due totlu^ filtering detritixore Sinuiliiiin sp. The second liiglu\st produc(M' xxas Bactis sp., but production was lai' loxxer than the black (lies (Table 5). The high [)r()duction ol simuliids in RS can be attributed to the presence of midtiple coliorts xxith short dexelopment times. Cirax' (1981) suggested that rajMcl dexelopment max' be adxantageous in streams subject to spates. 19921 iNsi'Xrr l'iu)i)r(Ti\ iTvix Sphixc-Sti^IvWi.s 21 Tahi.i: 9. (loiiiparatix-e whole stream .secoiulaiA production ol inscct.s (\\ <; l)\\'-m'~\T-l), e.xcept as indicated, in l'i\e i^eoc-liniatic resiion.s. Streams CTroiiped In' '^eograjihical region, not 1)\ temperature rep;inies. .Stream (;c Cr/.sc I'red Sonrc( Cold/mcsic Unnamed, Quebec Facton' Br., Maine Sand H., Alheita Caribou H.. Minnc^sota BlackliooC R.. Minnesota No. Branch C^r., Minnesota Fort R., Massachusetts Bear Br., Massachusetts L'Anee (hi Nord, France Bisbalh" Iniek, Denmark Huiiiicl/inesic .Satilla K. Ci-orgia' Snag substrate' SancK' substrate*^ Mud substrate' Cedar R., So. Carolina Lower Shope Fk., No. Carolina Upper Ball Cr., No. Carolina Bedrock-outcrop Riffle I'ool Hot de.seii S\camore Cr. .Xrizona New Zealand Hinau R. Horokiwi R. Cold desert DeepCr., Sta. 1. Iddio Dougkis Cr.. Wasliington Sni\el\ Spr.. Washington Rattlesniike Spr., Washington 5.8" Haqierl978 12.2 Nexes 1979 O.S" Soluk 19S5 3.54 ().S3 ().fS2 1.3fS 0.14 0.59 Kruegerand Waters 19S3 7.13 1.00 3.53 1,15 0.37 l.O.S Knieger and Waters 1983 13.23 0.73 5.33 9.43 1.00 2.07 Knieger and Waters 1983 3.3 Fisher 1977 4.8 Fisher and Likens 1973 12.5 (Total detriti\ore P=P - Fred.) 2.0 Maslin and Pattee 1981 26.7 1 .3 .Mortensen and Sinionsen 198^3 25.2 64.8 2.9 18.0 49.3 8.1 4.3 21.0 0 17.9 3. 1 17.9 0.2 8.6 9.2 3.0 0.1 1.0 1.3 0.02 1.4 0.6 6.1 0.6 2.1 2.1 0.6 0.7 5.6 1.4 0.3 1.8 1.0 1.1 7.6 2.4 0.03 3.0 o.:'^ 1.9 120.9 38.2 Hopkins 1976 41.5 Hopkins 1976 1.2 Minshalletal. 23.2 0.6 4.2 15.3 2.7 0.4 This stuck 14.2 1.3 3.2 9.3 0 0.3 This stuck 16.4 0.2 3.6 lis 0 O.S Thisstu(k Benkeet al. 1984 Smoeketai. 19S5 Ceorgian and W'lJkice 1983 Humi and Wallace 1987 Jackson and Fisher 1986 197.3 'S = sliredtlen Fc = filterins-cx)llecf()r; (..l = 'Kmergers onlv. 'Only two species of cliironomicLs. ' F.xprcs.scil per iinil .lira of total stream bott 'T,\prcssi'il pir ijiiil an-., oflialiilal. Hatlu C'oniparisons with ()th(>r Strc^im.s Annual IVB latios langcd Iroiii .3.6 to 121.7 lor insects from the studvstrcaiii.s. The high animal P/R ratios are attiibntetl to insects with rapitl (le\('lo])nient and multiple cohorts (e.ii;., main (."hironomidae). The annual P/B ratios lomid in thes(^ cold desert spring-streams arc generalK lower than those reported 1)\ fackson and I'^isher ( 1986) for Sonoran Desert stream insects and 1)\ Benke et al. (1984) for southeastcM-n hlackwater stream iiisc^cts. The .Sonoran and hhickwatcr streams are warmer and insect (k'xclopnient is faster, resulting in a greater iiumher of cohorts. Our annual P/B ratios wen^ geneialK hi'^hcr than reported for northern temperate streams (Knieger and Waters 198.3). wlien^ cooler streams result in insect dexelopment at slower rates with fewer cohorts. Total ins(>ct i)roduction rates in this stud\- ranged Irom 14 to 23 g DWuf-N r' and are compared with \alues for other streams grouped In geographical region (Table 9). Pro- duction rates in cold desert streams are well below the higher \alues found in New Zealand streams, the ricluM" areas (snags) of humid/mesic streams in the soiitheasteni United States, and Sonoran hot ck'sert streams. Howexer, produc- tion rates in cold desert streams are higher than those in stre.niis in cold/mesic areas of the I iiited Stales. These rankings relate to the int(Maclioii among stream water temperature, insect deNclopuKMit, cohort production inter- \als, and other factors. Howexer, it should be kept in mind that other factors, e.g., geochem- istn, ma\ be influential in goxerning production as well as temperature. Production \alues in oo Ghkat Basin Naturalist [y^ 52 Rattlesnake Springs, which has a sandy substra- tum, are comparable to the sandy areas of the Satilla Hi\er in Georgia (16.4 vs 13.1 g DW ni'"\r"\ respecti\eK); production of col- lector-gatherers was identical. Benke et al. (1984) stated that measurement ofsecondan' productivit)' ofbenthic organisms pnnides a tnier indication of their importance in lotic ecosNstems than does measurement of either den.sit\- or biomass. This is intuitively rea.sonable since measurement of P, a rate, includes consideration of both biomass and den- s\t\: Our results support the validit)' of Benke et al.s (1984) cf)ntention. (>learly, our data reveal that collectors are the dominant hmctional group, and detiitixores the dominant trophic le\el in terms of die secondan producti\it) of insects in the.se three streams (Tables 6 and 7). If onK biomass or (k'nsit>' data are evaluated from these streams (Tables 3, 4, and 5; Gaines et al. 1 989 ), anomalies become evident. Density- data in DC re\eal that herbivores are ecjualK' as numerous as detntivor(\s, but biomass data re\eal that detritixores are about two times greater than herbivores. Conversely, when the insects are separated into functional groups, the bicnnass of grazer/scrapers (herbivores) exceeds that of collectors in D(] h\ a factor of two. Further, collector-filterers in DC; represent 18% of the production and 30% of tlie biomass, but onl\- 7% of the densit\'. In SS, trophic level comparisons reveal that detritix'ores dominate production, biomass, and densit); but if hmc- tional groups are compared, biomass data would oxereniphasize the importance of shredders (30%), wliich form onl\ 5% of the densit)- and 9% of total production. In HS, the largest anom- aly appears when comparing functional groups. .Although collector-filterers represent 72% of the total production and 61% of the biomass, tlu^ir densit)' is similar to the collector-gathenMs. In c-onclu.sion, we ha\e found that taxaw id I short (k'x-elopment times and multiple cohorts, sucli as midges and black flies, are important to cold desert .spring-stream production. Pre\-ious studies ha\-e addressed the difficulties in obtaining accu- rate field estimates of Simuliidae (black flv) and ( :liironomi(kie ( midge) lanae CPIs, and duis pro- duc-tiou estimates (BcMikeetal. 1984, Beginner and Hawkins 1986. Stites and Benke 1989). Their small si/.e, rapid turnoxer rate, high densitx, and dixei-sit)' make accurate species-.specific CPI esti- mates difficult. These same characteristics, how- e\er, make midges antl black flies vetv importtmt to stream communities in terms of production. In nianv streams, thev contribute a large per- centage of the total community production because of their rapid development and liigh timiover rates. We found high P/B ratios for siniuliids and chironomids, but other inxestiga- tors luue reported similar results (Fisher and Gray 1983, Benke et al. 1984, Stites mid Benke 1989). This life-liistory strateg\- is particularK- advanta<2;eous for insects inhabitins; the streams that are subjected to severe spates. Detritus is the major food resource in these small streams; collector-gatherers predominate where there is more substratum diversit\- (DC and SS), and filterers in svstems more prone to the effects of spates (RS). Grazer/scrapers are present whenever suitable substratum and suf- ficient sunlight are available for development of a peripli)ton crop. Shredders, surprisingh-, are not well represented in these small headwater streams. This may be related to the flushing of the systems b\' the spates and/or the low amounts of allochthonous detritus reaching the streams (Gushing 1988). Secondaiy productiv- ity of these cold desert spring-streams was less than that of streams in hot deserts, but generally higher than that in most cold/mesic and humid/mesic .streams. FinalK', our results underscore the contentions of Benke et al. (1984) that measuring the secondan production of in.sects in streams piTnides a better iissessment of their role than densitv or bioniiiss, but the anom- alies described abo\-e argue for care in appKing this genenilization to all streams. Ac K N ( ) \ V L E D C; M E N T S This paper represents a portion of the thesis submitted b\-WLG to Central Washington Uni- \'ersit\- for the M.S. degree. The research was pcM-formed at Pacific Northwest Laboraton- during a North.west C^ollege and Uni\-ersit\- Association for Science (NORGUS) Fellowship (Unixersitv of W'ashington) to WLG. It was funded mider Contract DE-AM06-76- KL()2225 and was supported b)- the U.S. Department of Energv' (DOE) under Contract DE-AC()6-76RLO 1830 bet^veen DOE and Battell(> Memorial In.stitute. We would lik(^ to thank Dr. William Coffman for identif\ing the chironomids, and Dr. Pat Scliefter for identifN-ing the caddisflies. The manuscript was impro\ed b\' comments from three anonxnious rexiewers; our thanks to them. 1992] Insect Phoductin ity in Sphin(;-Sthi£ams 23 LlTERATURK ClTKI) An'DF.HSON. R. O. 1959. A modified flotation technique for sorting bottom fauna samples. l,imnoIoy> and Oeean- onrapliN 4: 22.3-225. B.\K TON. 1). R. 19S0. Obsenatious on l\tv lite liistorics and biolog\ of Ephemeroptera and Plecoptera in nortli- eastern All)erta. Aquatic Insects 2: 97-111. Becker. C. D. 1973. De\elopment of Siimtliuiit vittiitiiin Zett. (Diptcra: Simuliidae) from lar\ae to adults at thermal increments from 17.0 to 27.0 i'.. .American Midland Naturalist 89: 246-251. Beiimeh. D. J., and C. P. H.wkins 1986. Effects of over- head c;uiopv on macroinvertebrate production in a Utali stream. Freslns ater Biolog\- 16: 2S7-.300. Benke, A. C. 1979. A modification of the Ihnes method for estimating second;ir\- production with particukir signif- icance for multivoltine populations. Limnolog\- and Oceanography 24: 168-171. Benke. a. C and J. B. \\ ',mi:)E 1977. In defense of average cohorts. Freshwater Biolog)' 7: 61-6.3. Bfnke. a. C, and j. B. \V.\ll.\c:e 1980. Trophic basis production among net-spinning caddisflies in a south- ern Appalachian stream. Ecolog\-61: 108-118. Benke. A. C, T. C. Van Aj^sdall. and D. M. Gillespie 1984. Invertebrate productivit\- in a subtropical black- water river: importance of habitat and life histon. Ecologiciil Monographs 54: 2.5-63. ClifeoHO. H. F. 1982. Life cvcles of mavflies (Ephemeroptera), with special reference to voltinism. Quaestiones Entomologicae 18: 1.5-90. Ct'siiixc;. C. E. 1988. .Allochthonous detritus input to a small, cold desert .spring-stream. X'erhandlungen der Intemationalen Wreinigvm fiir Limnologie 2.3: 1107- 111.3. Clsiiinc;. C E.. and W. L. Gaines 1989. Thoughts on recolonization of endorheic cold desert spring-streams. Journal of the North Ameiiciui Benthological Societ\ 8: 277-287. GusiiiNC. C. E., imd E. G. Wolf 1982. Org;uiic energ\ budget of Rattlesuiike Springs. Washington, .\iiicrican Midland Naturalist 107: 404-407. . 1984. Piimarv production in Rattlesnake Springs, a cold-desert spring-stream. Hydrobiologia 114: 229- 236. GisiiiNc;, G. E., C. D. Mclntiue. J. R. Sedfli. )>:. W. GUMMINS. G. W. MiNSHALL. R. G. PETERSEN, and R. L. Vannotr 1980. Gomparative stuck of physical- chemical variables of streams using multi\ariate anak- sis. Archiv fiir H\ drobiologie 89: .343-.352. Fisher. S. G. 1977. Organic matter processing by a stream- segment ecos\stem: Fort Ri\er, Massachusetts. U.S.A. Internationally Revue gesamten Ihdrobiologie 62: 701-727. Fisiii i; S. (;.. and 1,. (.',. GnAV 198.3. SecondarvproductioTi and organic matter processing l)y collector macro- invertebrates in a desert stream. EcologN' 64: 1217- 1224. Fisher, S. G.,andG. E. Likens 1973. Energv- flow in Bear Brook, New Hampshire: an integrati\e approach to stream eco.svstem metabolism. Ecological Monographs 4.3: 421-439. Gaines, \V. L.. C. E. G\siiiN(;. and S. D. Smith 1989. Trophic relations and functional group composition of bentliic insects in three cold desert streams. South- western Naturalist 34: 478-482. (Jl.oHci \N r.. and |. 15. WALLACE 1983. Seasonal produc- tion (Knaniics in a guild of periph\ton-grazing insects in a southern Appalachian stream. l']colo_g\' 64: 12.36- 124S. (;i;\v L j. 1981. Species comjxjsition and life histories of aquatic insects in a lowland Sonoran desert stream. \merican Midland Naturalist 106: 229-242. 11 win.roN, A. L. 1969. On estimating annual production. Linmol<)g\' and Oceanograph\' 14: 771-782. IIaiU'ER. p. p. 197.3. Emergence, reproduction, and growth of setipalpian Plecoptera in southern Ontario. Oikos 24:94-107. . 1978. Variations in the production of emerging insects from a Quebec stream. Verhandlungen der Intemationalen Wninigun fiir Limnologie 20: 1.317- 1.32.3. llFMi'iULi. N., and S. D. GoooPER 1983. The effect of ph\ sical disturbance on the relatixe abundances of two filter-feeding insects in a small stream. Oecologia .58: 37,8-.382. Hopkins. G. L. 1976. Estimate of biological production in some stream inxertebrates. New Zealand Journal of Marine and Freshwater Research 10: 629-640. Hi HVN. A. D., iuidj. B. Wallace 1987. Local gcomorphol- ogy as a determinant of macrofaunal production in a mountain stream. Ecokjg)' 68: 19.32-1942. Hynfs, H. B. N. 1980. A name change in the sec-ondary production business. Limnolog\- and Oceanography 25:778. IIVNES, H. B. N., iuid M. J. Goi.E.MAN 1968. A simple method of assessing the aimual production of stream benthos. Limnologv- and Ocetuiography 13: .569-573. J.vcKsoN |. K., andS. C FisiiER 1986. SeconcLuy produc- tion, emergence, and export of aquatic insects of a Sonoriui desert stream. Ecolog\ 67: 629-638. Krlfc;er, G. G., and E. F. GooK. 1984. Lifecycles, stanckng stocks, and drift of some Megaloptera, Ephemerop- tera, and Diptera from streams in Minnesota. U.S.A. .\quatic Insects 6: 101-108. Ki4i FCFH, G. G.. and T. F. Waters. 198.3. Annual produc- tion of macroinxfrtebrates in three streams of different water qualitA. Ecolog\' 64: 840-8.50. Mack.w, R. |. 1969. Aijuatic insect communities of a small stream on Mont St. Ilihiire, Quebec. Journal of the Fisheries Research Board of C;anada 26: 1157-11(8:3. Mackfv a. p. 1977. Growth and dexelopment of lanal (;hironomidae. Oikos 28: 270-275. Maslin, J-L., and E. P.vitee 1981. La prockiction du peuplenient benthique dune petite ri\iere: son e\alu- ation par la mc'-thode de Hviies. Goleman et Hamilton. Archiv fiir IIy(lrol)iobgie.'92: .321-;34.5. .\I( AiLiEEE. J. R. 1982. Behaxior and life histon of Lcucotrichia pictipes (Banks) (Trichoptera: Hydroptil- idae) with spi-cial emphasison ca.se reoccupancv Gana- dian Journal of Z(x)log\ 60: 1.557-1.561. M( ci LLOLcai. D. A., G. W. Minsiiall. and G. E. Gt'sii- INC 1979. Bioenergetics of a stream "collector" organ- ism, Trinmithodcs miinttus (Insecta: Ephemeroptera). Linuiol()g\ and Oceiuiography 24: 4.5^58. Merri'it. R. \V., luid K. W. GXm.shns. eds. 1984. An intro- duction to the acjuatic insects of North America. 2nd ed. Kendall/Hunt Publishing Gomp;un. Dubuque, Iowa. Minsiiall. G. W. 1978. Autotrophy in stream ecosystems. BioScience 28: 767-771. 24 Gkeat Basin Naturalist [N'olume 52 . 19S4. Acjiiatic- iiisc'ct-siil)stratiiin rclalionsliips. Pages 358-400 in V. II. Hc-sh and D. M. Koseiiherg, eds.. The ecwlog\- of aquatic insects. Praeger Puhlisli- ers. New York. MiNsii.M.i.. G. W', D. A. Andkku s. F. L. RosK D. W. Shaw and R. L. Ni;\\ KLL 1973. Validation studies at Deep Creek, Curlew \ alley. Idaho State University Research Memorandum No. 73-48. MoKTKNsr.N. E., iuid j. L. Simonskn 1983. Pnuluctioii estimates of the henthic invertebrate conniiunity in a small Danish stream. Hvdrobiologia 102: 155-162. Nk\ Hs R. J. 1979. Second;ir\- production of epilithic fauna in a woodland stream. American Midland Naturalist 102: 209-224. O'lIoR J.. J. B. \\'ai.1..\(.f.. and J. 1). Haki'NKH 1984. Production of a stream shredder, Pcltopcrla inaria (Plecoptera: Peltoperlidae) in disturbed and undis- turbed hardwood catchments. Freshwater Biologv 14: 13-21. Smock. L. A., F. (Jilinskv, and D. L. Stoxkbl h\7-.k 1985. Macroinvertebrate production in a southeastern United States blackAvater stream. Ecolo'^v fi6: 1491- 1503. SoiA K D. A. 198.5. Macroimertebrati' abundance and pro- duction of psammophilous Chirononiidae in shifting sand areas of a lowland river. Cixnadian Journal of Fisheries and Aquatic Sciences 42: 1296-1.302. SniKs. D. L., and A. C. Bf.nkk 1989. Rapid growth rates of chironomids in three habitats of a subtropical black- water river and their implications for P:B ratios. Lini- nolog)' and Oceiuiograpln- 34: 1278-1289. \V/\TF,HS. T. F. 1977. Secondarv' production in inland waters. Advances in Ecological Research 10: 91-164. Watkks, T F., and J. C. Hokenstrom. 1980. Annual pro- duction and drift of the stream amphipod Gainiiiants pseiidohtnnacus in \'alle\ Creek, Minnesota. Lininol- og\' and Oceanograph\' 25: 700-710. Received 1 ]nnc 1991 Revised 1 December 1991 Accepted 10 Jannan/ 1992 CJreat Basin Naturalist 52; m)-i 25-28 EFFECT OF REARING METHOD OX CIIUKAR SI :R\'1\ AL BartclT. Slaiidi laii \. I* lin |a\ A. Roherson' , and X. I'nil |( AUSTHACT, — Sun i\al nl adult cliukar-iuiprintcd. >j;anic tarui isil)liii'hnkars (Ihnkars (same genetic stock as the adult- imprinted birds) xxere rai.sed at the Utah Dixi- sion of W ildlife Resources (DWR) C^ame Farm in Springxille, Utali, under conxentional meth- ods (broock'd in l)ox-tx]-)e brooders, fed and watered xxith humau conlacl [sibling/hnman- imprinted], antl moxcd into ni second studv site was the Sterling IIollowA\ind Rock Ridge area of Spanish Fork Canyon. This area ranges in elevation from 1470 m to 3057 m, and the dominant ecological t)pe is mountain brush. Annual precipitation a\erages between 38.8 cm and 52 cm. Average yearly high and low temperatures are 40 C and -30 C, respecti\el\. On 25 September 1989 (release II), 1 1 birds Ironi each group were radio-marked and released at site II. Captive-reared groups were 21 weeks old. Mortalit) was recorded daiK for t^\'() weeks, then weekK thereafter. Statistical AuaUsis Data were anaKy.ed using a Product limit (Kaplan-Meier) estimator; a k)g rank test was used to compare sunixal cui-ves (Pollock et al. 1989). Onl) radio-markt>d birds were compared since their obsenation was not biased b\ ea.se of approach and proximit)- to release site. Results Release 1 All adult-imprinted and game farm chukars (both radio and patagial tagged) died within three weeks of release (Fig. 1) with no differ- ences between groups (P < .05). Wild birds decreased in number shortly thereafter but experienced higher sunival rates (F < .05) than captive-reared groups. Coxote predation was the principal cause of mortality. Release II There were no significant (F < .05) differ- ences (Fig. 1). Release III Mortality was similar (F < .05) for the adult- imprinted and wild groups but higher (F < .05) for game farm chukars (Fig. 1). All Releases Combined data for releases 1, 11, and III indi- cate similar (F < .05) suni\ al for wild and adult- imprinted groups, both having higher (F < .05) \alues than game farm birds (Fig. 1). Discussion During relciLse 1, wild birds mo\ed (juickh' to high, I'ockA areas, whereas captive -reared birds remained at lower elexations and sought co\'er in the sp(U\se vegetation, where they suffered liigh mortalits'. Immediatelv following demise of cap- ti\e-reared birds, wild birds began to be killed. Adult-imprinted and wild birds demonstrated the greatest fear response to human presence, whereas game farm birds tolerated approach. These findings correspond with those of CsenneK' et al. (1983), who found that red- legged partridges {Alectoris nifa) displaved greater fear response toward humans when iso- lated from them during imprinting. The flight- ier behaxior of the adult-imprinted chukars would likeK' proxide more hunting sport than game farm birds but did not offer sufficient suivix al ad\ antage under the existing predator j)r("ssur('. Adult-imprinted birds appareiitK had a behaxioral adxantage over the game farm birds tliat was not ex|oressed in release 1 but was demonstrat(Hl at release II, apparentK due to lower prcxlator pressure. Wild chukar m()rtalit^• was similar for releases I and II. 19921 CiiikAH 1U:ari.\(; 27 RELEASE RELEASE II ■ Adult imprinted O Game farm A Wild RELEASE ALL RELEASES Fig. 1. Chiikar sunival prohahilitN cuncs: i 1 i release I ( Aiitt-lope Islainl. S August-15 Noveniher 19S9) — no difference (P < 0.5) between game larni and adult-imprinted elmkar.s. hut botli group.s are lower than wild ehukar.s; (2) release II (Spanish Fork Canyon, 5 Septemher-12 December 1989) — no differences (P < .05) between gronps; (3) relea.se III (Antelope Island. 2 May-S Augnst 1989) — no differences (P < .05) between adult-imprinted and wild, but lioth groups are higherthiui game form chukars; (4) all releases — no differences (F < .05) between adult iiiiiiriiited and wild, but k)wer for iiame farm chukars. Re.sult.s irom rcle;i.se III iiulicated tliat .sur- vival on Antelope Island for all groups was greater than in the prexious \'ear, especially for the a(lult-ini[)rintecl group. The iinproxcnu^nt was attributed to predator remoxaf wliieli nia\ he heneficial e\en in establishing transj)huit(Hl wild birds in good habitat. Season ot the year ina\ ha\'e affected sunixal as altematixe pre\' abunchmce and predator location on the island nia\ ha\e \aried. |()nkel (1934), however, obsened little difference in chiikar siuAival related to sea.son of release. Combined data from all releasees suggest that captixe-reared chukars can be used to establish wild populations if gixcn properearlvbehaxioral conditioning. This stiuK, howe\er, does notpro- \ ide intorniation on reproductive success. ACKNOW LFDCMF.XTS We express appreciation to the Utah Dixision of Wildlife Resources for project hmding, also to M. A. Lar.s.son and J. Fillpot (Utah Dixision of Parks and Recreation — Antelope Island State Park) and BYU and DWR personnel who as.sisted with the project, and to C;. C. Pi.\ton (BYU Statistics Department) for statistical assistance. IJTFHATI'I^K ClTFD H\ii i;v K. D., and K. M. Rm.imi. 1975. The effects of embiAonic exposure to pheasant \ociJi7,ations in later call identification bv chicks. Canadian |ournal of Z(X)I- og\ 53: 1028-1038.' 28 Ghkat Basin Naturalist [N'olunie 52 CSF.HMKLV. D., D. Mainakdi. andS. Si'ano. I9S3. Escape- reaction of captixc \oung recl-Iej;j;ecl partridges {Ah'ctoris nifa) reared with or without \isual contact witli man. Applied Animal Etholog) II: 177-1S2. DouKl.l. S. 19S9. Hearing and prcdation. The Game ('on- senancN Amiiial Ri'\iew 20: -iol()i^ . IJriijhani Yoiini; Uni\i-rsih'. rro\(>. Ulali. ■ Departiiieiil of Biolog). Boisi- State Uiii\crsit\ Biiise. Idaho. 29 30 Great Basin Naturalist [X'olume 52 TMil.K 1 DNA viekls froin fbmialin-fixed musetim spednieiis ofcuttliroat trout {Oncorhijnclius riarki). DNA \ields were tlcteriiiiiH'd iisinij l)\' spcctroiiieter ahsorliance readings at 260 niii. Saiuple Total DNA tissue weight DNA vie Id Sill )S[X'C'ic's ^ear Location Museum No. t\pe (g) (f-g) (|jig/mgtis.sue) o. c. hoiivirh 1926 Snake R.. ID BYU #26792 li\c'r 0.13 77.5 0.59(1 o c. ntali 1927 Utah L.. UT BYU #26755 ii\(T 0.64 567.5 0.887 o c. iitali 1940 Utali L.. UT BYU #26756 liver 0.65 310.0 0.477 o r. iittilt 1982 Deaf Smith, UT BYU #176896 uiusele 0.24 147.5 0.615 o. r. iildli 1982 Deaf Smith. UT BYU #176890 gut 0.42 965.0 2.298 o. c. Utah 1928 Trout Cr.UT BYU #26858 li\-er 0.07 51.0 0.728 o t: Utah 1981 DeepCr. UT BYU #176793 muscle 0.11 57.5 0.523 et al. 19S5). The bufft^- was changed twice oxer 24 hours. Fin Tissues Fin tissues were taken from anesthetized hatcheiA rainbow trout {Oncorlu/nchtis i)u/kiss) that ranged in length from 15 to 25 cm. Samples were taken from all (ins hut were restricted to the outer edges of the fins to more accnrateK represent the region that would he sampled in the field. ApproximateK 1 cm" of fin was remo\ed for each sample. These were placed in labeled 1.8-ml poKetlnlene tubes with gas- keted screw caps. Four sample's were taken for each of si.x treatments applied to the fins. These were (a) 10% formalin, (b) 40% isopropvl alco- hol, (c) .storage in a standard freezer at -20 C, (d) storage in an ultracold freezer set at -80 C, (e) 70% ethyl alcohol ( Et( )H ), and (0 air-dning. The samples were held in the tubes for 45 da\s, after which the presenatives were decanted and the tissues soaked in TE9 for 24 hours, with no change in the buffer. The frozen and air-dried .samples were not soaked in buffer piior to extraction. One sample stored at -20 (] was lost during storage. Extraction Pn )cedme Tissue samples were minced with a clean razor blade (to 2 mm or less in cross section) and placed in 15-ml centrifuge tubes with 10 ml of TEyandO.I gof SDS. Fixe mgofproteina.se K xvas ackied to each sample, and the tubes were cappi'd and incubated in a shaking water bath lor 24 hours at 55 C. An additicmal 5 mg of proteinase K and 0.1 mg SDS xxere added to each .sample and the tubes returned to tlu> shak- ing water liath for 50 hours at 55 C to remoxc residual undigesteil tissue. The samples xvere transferred to 30-ml tubes, and an equal xolume of phenol-chloroform xxas added to each. The tubes were inxerted sexeral times to mix and then centrif uged in an SS-34 rotor at 10,000 ipni for 10 minutes. The aqueous phase from each sample xxas remoxed xxith an inverted glass pipette and placed into clean 30-ml tubes and the procedure repeated. A final extraction of the acjueous phase xx'as made xvith one xolume of chloroform and centrifused as liefore. The aqueous phase from each sample xx^as trans- ferred to a new tube and .1 xolume of 3 M sodimii acetate solution added. The mixtures xvere precipitated xx'ith one xohmie of 95% EtOH and .stored at -20 C oxemight (12 hours minimum). Each sample xvas centrifuged at 10,000 ipm for 10 minutes and the supernatant carefullx poiu'ed off, leaxing a DNA pellet. The pellets XX ere xxashed xxith 70%- ethvl alcohol and centrifuged again for 10 minutes at 10,000 ipni. The alcohol xvas poured off and the samples alloxx'ed to air drx; The pellets xx^ere resuspeuded in a 3 mM Tri.s, 0.2 niM EDTA solution (pH 7.2). RNase xxas added to a final concentration of 20 |jLg/ml. Results and Discussion .Archixed Specimens Mu.scle and lixer tissues xielded comparalile amounts of l^NA, and exceptionallx high xields xvere obtained from the sample of gut tissue (Table 1 ). Because the gut tissue xx'as xx'ashed in buffer immediatelx after remoxal from the pre- .serxed specimen, contamination from items in tlu> alimentaiy- canal should haxe been minimal, (wit tissue xxas easilx' digested, indicating a rel- atixely rapid relea.se of DNA (Diibeau et al. 1986), and this coidd haxe been associated xxith the high xields. DNA samples (20 |xl) from the museum specimens xxere electrophoresed on a 1992] D\A FROM Phi:sfr\ei:) Thout 31 B m % ^ s 9^ fli Fig. 1. DNA eleetrophoresed on 1% agarose gels after being extracted (Fig. lA) from formalin-presen'ed innsenm specimens and following PCR amplification ( Fig. IB). The DNA from the trout collected in 192fi ( liver) is only faintk' visible (lane 1, Fig. lA). The DNA from 1927 (liver), 1940 (liver), 19S2 (mnscle), luid 1982 (gnt) are in lanes 2-5, re.specti\el\-. The DN.\ in huie 6 was extracted from a contemporary frozen liver sample. The PC'R prodncts are shown in Figure IB. Lanes 1-6 in Figure IB correspond to the D\'.\ tc^nplates shown in lanes 1-fi in Figure l.\. TvHi.K 2. .\ comparison of the nucleotide sequence (120 ba.se pairs) from the SD-1 region oi the mitochondrial DN.A il-loop. The DNA was amplified with the polvmerase chain reaction. The top row represents the base sequence from frozen-tissue DNA, and the lower row represents the sequence from a formalin-preser\ed specimen. The frozen-tissue specimen (BYU #90621) is O. r. ittah. from McKinzie (]reek, IT, collected S-I7-S8. The preser\ed-tissue specimen ( BYU #26755) is O. c. utah, from Utah L., UT collected in 1927. Both vouchers are aicliivcd in tin- fish range at the Monte L. Bean Life Science Museum. l'"ro/en l^reservcd A A c; c; c TAT c; c: A A G G C T A T C C A c; c c G A A c; T A A G C C G A A G T A C A A T C T T A T T G A A T C: T T A T T GGGTTGTGTT GGGTTGTGTT T T \ .\ C; A A A G G T T \ \ G A A A C C A A(;G ATGTGG A A G G A T G T G G C; G G G G T T A G C: C; G G G G T T A G C: A TAT C; A G T A C; A T A T (; A G T A C; A c; G c; c: g t c a a 30 a g g g g g t c; a a ttaatg(;tgt 6o ttaatg(;tgt gaggaag(:g(; 90 g agg aagggg ggggtgtggg 120 c; c, G c: T c: T G G G \7c agarose gel containing etiiidinni hromidc ( Fig. lA) to verify extraction. The DNA samples extracted from fresh and presened tissne sam- ples were nsed in a P(>H reaction (25 jxl total \()hnne) nsing primers for the d-loop region ol front mitochondrial DNA dexeloped b)- K. Thomas (Universit)' of California, Berkeley), with standard conditions (Perkin Elmer Cetns. Non\alk. (lonnecticnt). C>\cle times and tem- peratnres wtM-e I iniinite at 92 ( ,', 1 minute at 53 (>. and 2 minntes at 72 C, for 35 c\cles. PCI^ products are showni in Figure IB. DNA extrac- tion controls containing no fish tissue did not \ield PCR products under identical conditions (data not shown). Subsamples of the PCH prod- ucts from preserved and fresh tissue samples were secjuenced (Fig. 2) and compared with contempoiaiA secjuence data from cutthroat trout (Table 2). Tlie .sequence data were identi- cal, indicatingthatwithin the amplified segment no base niodilicafions had occurred in the for- malin-present hI samjile. Fin (;lij)s We obtained DNA from all fin clips regardless of presenation method. Mean \ields ranged from a low of 0.40 [xg/mg of tissue from forma- lin-preser\ed fin clips to a high of 1.104 |JLg/mg in air-dried samples (Table 3). The treatment effects were examined with anak sis of \ariance ( Table 4), and a highly significant difference was found bt>t\\e(Mi the treatments. Fishers least significant difference multiple comparison pro- cedure w as applied to separate those treatment 32 Great Baslx Naturalist [V'« olunie o'l B Fig. 2 (at left). Sequence gel from a portion of the mito- cliondrial l^NA tl-Ioop. (Joluuin A i.s the .sequence for a conteinporaiT sample of trout DNA (BYU #90621) and coluum B is the ,se(juence from a preser\-ed trout specimen I BYU #26755) collected in 1927. The sequence ge! is read from the hottoni up, and the colunms represent guanine (G), adenine (A), tliNininc (T), and c\tosine (C), respectix-elv. Q. O Q. O W3 :CM O ^o O^ 00 p T3 CO — r" 0.50 0.25 0.75 1.00 1.25 mean DNA yield {^ig / mg) Fig. .3. Multiple comparisons of the means of the six fin tissue treatments, using Fisher's leiLst significant difference test (alplia = 0.01 ). Lines connect means tliat do not differ siiruilicautK from one another. Tabi.K .'3. DN.^ \ields Irom fui tissue presened with dif- ferent methods. The lin clips, approxiniateh 1 cm" each. were taken from hatchen -reared rainhow trout {Onctirhi/iicliiis im/kiss). D\\ \ields were determined using U\' spt'ctrometer alisorliance readings at 260 um. I'resen atiou N Mean Stantlard metliod \ield ( (JLg/uig) deviation formalin 4 0.402 0.15743 40';^ isopn)p\l 4 0.569 0.19111 -20 c: ■3 0,644 0.10016 SOC 4 0.740 0.06295 70'7r KtOlf 4 0.S22 0.07964 air-dried 4 1.104 0.13443 a i;;r()ui),s that clifFei-ccl significantK From one another. Tho.se compansons (Fig. 3) indicate that the air-(hi(xl treatment ga\e \ields signifi- eantlx higliei- than the other treatment.s. Becan.se the weights used in ealenhiting the DNA yi(^hls were the preextraetion \ahies and not the pretreatnient weights, the initial weights (pre(hAing) of the air-ch-ied samples are not known. I lowexer, ha.sed on the initial si7,e of the tin cli})s, tliey are assnuied to \\a\c heen similar". WTiile air-dnini: \ields ar(> nmch better tlian 19921 DNA Fwnw PRKSEn\i:D Troit 33 T\Hl.l'4. ()iic-\\a\ aiial\sis ol \ariaiuc ot tlic Ihi clip ticatinciit clictt on DNA \i('l(l. Source Degrees of freecloiu Sum of scjuiU'es Mean sfiuare Prob. > F iVcatuient Error Total! ad j) 17 9.1 1.14512 0.2891 1 1.43424 0.22902 0.01700 I3.4'; O.OOCX) tlio.si" resiiltiiiti; Iroiii other prcsenatioii iiiclli- (xls. the lack ol preseniitixes could allow socoiulaiA foiitaniiuation of samples through l)aet(Mial or luugal colonizatiou, aud air-dning prohahK should not be used in collecting sani- j)les in humid areas or where adequate storage is not possible. The yields obtained from ethyl alc-ohol presi^iAation are equal to those from hozen tissues and superior to both isopropxl alcohol and formalin presenation. Of the pre- senati\"es examined in this studx; eth\'l alcohol would appear to be the preservative of choice in most field situations. This eliminates the neces- sit\- of earning drv ice or lic|uid nitrogen into the field to presene tissues. Other presenative solu- tions should be considered; for instance, Seutin, W'liite, and Boag (1991) reported successful DNA extraction from a\ian tissues presened in a mix- ture of EDTA, NaCl, and DMSO. Conclusions The abilit\ to extract, amplif\; and sequence D\,\ from formaliu-presened museum .speci- mens increa.s(^s the inloriuation value of mu.seum holdings. In addition tol)eingarecordof moipho- logical and meristic information, the specimens can l)e u.sed in biochemical studies. Because museum collections include hpe specimens, rare spcx'ies, and representatives of now extinct fonus, many ke>' phylogenetic relationships can be reex- amined. The extraction techni(|ues can be applied to contemporan pr(\s(M-\ed tissues as well. Fin tissues gi\e ade(juate \ields with this techni(jne for 1 )oth restriction enz)'me digestion and P( A\ ampli- tication. Fin samples, which can be taken nonleth- alK. present opportunities to examine fish populations that would othenxi.se be inaccessi- ble to tissue collection becau.se of management considerations. LlTKKATliHK CiTKD Di:hi:ai L., L. A. Cii wdi.kh J. H. CiUAi.ow. I^. R. Nu.ii- ()l,s. and P. A. Jonks 1986. .Soutliern hlot analysis of DNA extracted from fonualin-lixed patliologs' speci- mens. Ciuicer Research 46: 2964-2969. CoK 1/ S. E., S. R. ri\.\iii.T()N. and B. \'()c;ki.stkin 198.5. Purification of DN.\ from fornialdelnde fixed and par- affin embedded human tissue. Biochemical and Bio- ph\sical Research Conununications 1.30: 11 8-126. Iloi l)i: P. and M.J. Bk.M N 1988. Museum collections as a source of DN.V for studies of a\i;ui phxiogein. ,\uk 10.5: 77:^776. Kociii.ii T D.. W. K. TiioM.vs. A. Mf.ykh. S. \'. Eowahds, S. I'wHo. F. X. \ ii.i.ABi.ANCA, and A. C. Wn.soN 1989. D\namics ol mitochondrial DNA e\<)hition in animals: amplification and sefjuencingwith con.served primers. Proceeding ol the National .Acadenn of Sci- ence 86: 6196-620(). .Ml l.i.is. K. B., luid F. A. Fai.oona 1987. Specihcs\nthesis of DNA in vitro \ia a poKinenuse-cataK zed chain reac- tion. Methods in Enz\inolog)' 1.55: 3.3.5-.3.5(). .Ml 1.1 IS K. B., F. a. Fai.oona, S. Sciiahk. R. Saiki C. lloHX, and n. A. ElU.lcil. 1986. Specific enzxniatic amplilication of DN.A in ritro: the poKinera.se chain reaction. Cokl Springs Harbor ,S\mposinm on Qiianti- tati\ e Biolog) 5 1 : 262-273. S.Mki R. K., D. II. Oi'.i.ANn S. Srcnri;, S. |. Sciiakf R. IlKaciu G. T. IIOKN K. B. Mllijs. and II. A. Ehi.ICII 1988. Primer-directed enz\niatic amplilica- tion of" DNA with tlu-nnostable l^N.A polvmerase. Sci- ence 2.39: 487-49 1 . S\iKi. R. K., S. Sciiakf. F. Fai.oona. K. B. Mi i.i.is. C. IIoHN. II. A. Eklicii. and N. Ahnhf IM 198.5. Enz\- matic amplification of B-globin genomic secjnences and restriction site aiiaK sis of sickle cell anemia. Sci- ence 2.30: 1350-1.354. Skitin. C, B. N.Whitk. and P. T. Boac; 1991. Presi-rva- tion ola\ ian blood and tissue samples for DN.V analysis. (Canadian Journal of Zoolog\' 69: 82-90. Thomas. W. K.. and A. T Bfckfnhacii 1989. N'ariation in salmonid mitochondrial DN.A: exoltitionan constraints and mechiuiisms of substitnticjn. Journal ol .Molecular Exolution 29: 2.3.3-245. WiiiTF. T. J., N. Aknmki.m. and II. A. Eklicii. 1989. The poKinerase chain reaction. Trends in (Jenetics 5: 18.5- 189. W'oNc.C. C. E. Dow I, INC li. K.Smki R. C;. Hick hi II. A. ElU.lCll. and II. II. Ka/.a/ian 1987, Oharacteri/ii- tion of B-thalassaemia mutations using diri'ct genomic secjuencing of amplified single c-op\ DN.\. Nature. 3.30: 3S4-386. ' 34 Grkat Basin Naturalist WiuscnN.K, L. A., R. G. H.glchi M. Stonek.ng, H. A. EHI..CH, N. AHNHKiM. and A. C. Wilson. 198/. Length mutations in hum^ mitochondnd DNA: direct sequencing ol enz)'matically aniplitied DNA. Nucleic Acids Research L5: .529-542. [Volume 52 Received 27 ] tine 1991 Revised 10 Febnianj 1992 Accepted 20 Febnianj 1992 Crcat Hasin Naturalist 52( 1 1. 1992, pp. 35^40 RELATIXC; soil. CIIKMISTHY AND PLANT RELATIONSHIPS IN \\ OODED DRAW S OE THE NORTHERN CiREAT PLAINS Mumierite E. Nborliees and Daniel W. Urcsk \.-2 Ahsthact — Soils of till' ijrccn asli/c'liokcclicrn liahitat t\pc in iioitliwcstnii South Dakota were cxaluatcd lor 22 properties to deterniine whether an\ could he correlated with densit\ ol chokeeherr\ il'miiiis vin^iiiiana) ami siiowhern' iSiiiitplioricdrihts occidcntalis). Siirfaee soils were moderateK teitile, with liiiili levels ol all elements except phosphorus and nitToij;eu. Soils wfre tine textiH'ed, with uioderateKhigh cation exchange capaeit\' anil saturation percentages. Ilowex'cr, soils \MH' nonsaline-nonalkaline with low amounts ol exchangeable sodium. None of the soil properties showed good eonclation w ith ehokeeliern and snow hern densities. (Greatest correlations were loiind between each of the shrub species Kci/ U(ir(l\: uixxlrd (Imws. <^rccii ash. slinihs. i^runus \irginiana, Sxniphoiieaipos oet-identalis. '^raziiit. Wooded draws constitute a Naluahic liahitat (\ |K^ ill the northern Great Plains. The\ pro\ide shelter from wind and weather and contain L;;reater moisture than surrounding areas, result- ing in an abundance of plant life and forage. An understanding of soil-plant relationships of tiiese wooded draws has become more critical since these areas ha\e been obsei^ved to be in decline (Boldt et al. 1978) for a \"ariet\" of rea- sons (Girard et al. 1987). Studies that correlate habitat t\pe with soil properties are particularl)' useful in efforts to manage these systems. Knowledge gained from such studies might help managers determine (he potential habitat t\pe of a site after \egeta- tioii decimation. Pfforts and limited resources could then be concentrated on sit(\s with the greatest potential for rehabilitation. This studx' was conducted to characterize the surface soil chemistiA' of the grecMi ash/choke- cheriT (Fraxiiiiis pcnnsi/lcanica/pmniis rif^iiii- (iHd) habitat tA'pe in northwestern South Dakota and to n^latc^ these soil properties as well as grass co\cr to (leiisitx ol chokechei'n and snowbern iSiiinplioiicaiyos occidcntalis). This habitat type is considered a topographic climax (Hansen, Hoffman, and Steinauer 19S4. Hansen and Hoffman 1988) and is one of the most important in the northern Great Plains. Si IDY .\Hi: A The stud\ areaisap])ro\imatel\ 5 miles north- west of Bison, South Dakota, in Perkins Count\' on lands administered b\' the USDA Forest Senice, Custer National Forest. Geologx of the area has been described In I lansen (1985). The topography is rolling to stec^p plains dissected b\- streams and drainagewaws. The climate of the area is characterized b\ warm summers and \er>' cold winters. Annual ])recii)itati()n axerages .36 cm, witli most receixcd in the spring and sunniuM". The habitat txpes ol the area ha\e been described l)\ Peterson (1987). The green asli/chok(X'hern habitat t\pe was found on shal- low to moderateK dee[). well-drained, Cabba- Lantn loam soils of upland ridges and the sides of steep drainagewa\s with slopes of 159^ to 40%. Mktiiods Gollection ol Samples Soil samples were colKx'ted during the summer of 1986 from 24 green ash/chokechern' diaw s spaced oxer a 2769-ha pasture. The \eg- etation ol (he 24 wooded draws ranged from few trees and shrubs (o a dense ox crstoiy and under- stonol trees and shnibs. Sampling was conducted L'SD.X Forest Senice. HockN Mi :it),, Soudi Dakota .5770 1. "Corresponding aiitlior. and Kans;e F.\periMienl Station, Soulli Dakota Seli(K)l ol'Mines and Teclinoloirv . .501 P.. St. Joseph St.. Kapid 35 36 Cheat Basin Natuhalist [Volume 52 TaBI.K 1. Cheinic-al nrop-itii-s of soil samples collected from ijrceii asii/cliokecliern liahitat h pe near Bison. Sontli Dakota (n = 72). Soil pll IX'. (mmiios/cni) Ori^aiiic matter {%) N0.5-N ((xg/g) P(m.,u;/U) Zn (ML,n/g) Fe (jtg/g) Mn(fjLg/g) Cii(|j.g/g) Ca(meq/I) Mg (meq/1) Na (iiieq/l) SAR Saturation i%) CEC(me(i/l(X)kg) Ext.'Ca(mg/kg)' Ext. Mg(ing/kg) Ext. Na(mg/kg) SaiulC/f) SiltC/f) Clav(7f) Meiui 7.3 0.6 9.1 3.1 2.5 321 3.4 21.2 7.6 2.1 4.5 2.1 0.2 0.1 72.9 45.2 4311 684 15.2 32.9 40.8 26.3 l^aMtre 6..3-7.S 0.4-2.6 4.2-19.8 1.0-17.0 0.1-10.5 202-491 0.9-9.2 6.9-268.0 3.2-24.1 0.,8-5.6 2.0-20.8 1.0-12.5 0.1-0.9 0. 1-0.2 48.8-106.5 29.9-62.4 2580-6830 90-987 1.8-57.5 20-67 21-51 11-40 Standard deviation 0.3 0.3 3.3 2.6 2 2 67 2.0 31.5 3.4 0.8 2.3 1.4 0.1 0.1 11.2 7.6 937 171 I . I 9.1 5.4 6.2 K\tr;iclal>ltc.i(i( at tliree locations in each draw. At each location (approxiniatek' 250 m"" in area), three frames (20 X 50 cm) were randomly located. Stem den- sities of chokechern at tlu^se locations ranged from low (0-2 stems/frame), to medium (3-6 stem.s/frame). and high (greater than 8 stem.s/trame). All stems were counted within a frame and the three \alues axeraged for each location. Canopy cover of grass was estimated in each frame (Daubenmin* 1959). One soil sample was collected within each frame to a depth of 10 cm. The t]\wc soil samples from each location were comhiiunl lor chemical anal- ysis, xielding a total of 72 samples. Soil .\nal\ses Amounts of 'soil elements (R K, Zn, Fe, Mn, (Ju) were determined In' using the annnonium hicadionate-diethylenetriamine pentaacetic acid (AB-DTPA) extract (Soltanpour and Schwab 1977) and iuducti\el\- coupled plasma atomic emission spectrometr\- (ICP-AES) (Jones 1977). The AB-DTPA procedure was de\-eloped and is used by the C:()lorado State Unixersit) Soil Testing Laboratory An ecjual amount ol pota.ssium is extracted as with the ammoniuui acetate test (Knudsen et al. 1982), antl the same amount of iron is extractcnl as with the standard DTPA test (Haxlin and Soltanpoiu- 1981). Half as much phosphonis is extracted using AB-DTPA as in the sodium bicarbonate extract (Olsen et al. 1954), and slightly less zinc is extracted than in the standard DTPA test (Ilavlin and Soltanpour 1981). AB-DTPA extractable copper and manganese are highly correlated with DTPA-extractable le\els of these elements (/•" = .75 and .86, respecti\'ely) (Soltanpour and Schwab 1977). The pH was measmed with a pH meter that used a combination electrode on a saturated past(\ Sodium adsoiption ratio (SAR) was esti- mated from lexels of soluble calcium, magne- siiun, and sodium measured in a saturation extract In means of ICP-AES. Total soluble salts were nunisured on the filtered extract with a solubridge. Organic matter was (U^ermined b\ wet oxida- tion with spontaneous heat of reaction. Potas- sium dichromate and concentrated sulfuric acid were us(>d lor organic matter, and results were determintxl calotim(4ricalI\. Nitrate nitrogen was determined In the chromotropic acid method. Le\els of extractable Ca, Mo and Na w ere measured In using ICP-AES on an annno- niiun acetate extract. Cation exchange capacity' was determined b\ the .sodium satiuation method (Page 1982)'. [992] Soil. ClIKMlS Tin \\n Fl.AXT Rklatioxships 37 Statistical AnaKses Simple linear regression was nsed to relate soil clieniistn \ariahl(^s to cliokecliern and snow- l)err\' densities; the points were plotted to clieek tor nonlinear relationships. Stepwise regression was nsed to test relationships between soil eheniistn; canop\ eo\(^r of grass, and densit\ ol each shnil). The regression model Y = a + 1)\'^ pi-o\ided the best fit in relating chokechern and snow bern densities with canop\- eo\"er of grass. Soil \ ariables and densities of both shrnbs were subjected to a nonliierarchieal cluster analvsis (ISODATA) to group the sites (Ball and Hall 1967). Stepwise^ disciiminant anaKses were nsed to estimate compactness of clusters and identifv the ke\ xariables that accounted for their differences. However, cluster anaKses and discriminant anaKses and simple correlation plots did not pro\ide an\- meaningful results. KHsri;rs .wd Discussion Nitrate nitrogen lexels averaged 3.0 fxg/g and ranged from 1.0 to 17.0 |xg/g (Table 1). Soil organic matter ranged from about 4% to nearlv 2()7c. These \alues compare well with values tiom surface soil samples from hardwood forest on fine-textured .soils (Charle\' 1977). Organic matter le\els ranged substantiallv higher than tho.se from soils from similar sites in North i^akota (Han.sen, Hoffman, and Bjugstad 1984), Montana, and South Dakota (Hansen and Hoff- man 1988). Nitrate le\els appeared ade(juate lor growth of rangeland plants ( Soltanpour et al. 1979). Soils were near neutral in pH (Table 1) and similar to other sites in Montana, North Dakota, and Soutli Dakota (Han.sen, HolTman. and Bjugstad 1984. Hansen and Hoffman 1988). A\ailabilit\ of nutrients at this pH is near maxi- mum except for Fe, Mn, Zn, and i'.w. which l)ecome less a\ailable alxne pH 7.0 (Brad\ 1974). Plants nsnalK' grow well bet\veen pH 5 and 8.5 ( Donahue et al. 1977) if no other growth factor is limiting. Phosphoins and potassimn content a\ eraged 2.5 jJ-g/g and 321 |i.g/g, respec- ti\('l\. Thus, phosphorus le\els were low, whereas potassium, /iuc, copper, and manga- nese levels were high (both generallv and rela- ti\e to similar sites in the northern Hi";h Plains [Hansen. Hoffman, and Bjugstad 1984, Han.sen and Hoffman 1988]). Iron Itnels a\ eraged 21.2 M-g/g and were fairl\- high. The cation exchange capacitx (CEC) was rather high at 45.2 meq/100 kg (Tiible 1 ). Cla\s in these .soils are likelv to ha\e high adsorptixc^ capacities since organic matter content and cla\ content did not fulK account for the high (>EC (BracK 1974). The sodium adsorption ratio (SAB) indic-ated iiiiiiinial saturation ol (he exchange c-omplex In .sodium. Electrical con- ductixity was low at 0.6 mmho.s/cm. The.se soils woukl be classed as nonsaline-nonalkaline with low ek'ctiical conducti\it\' and exchangeable sodium percentage. The saturation percentage at 72.9 was somewhat higher than othcM" nonsa- line-nonalkaline^ soils in this classification ( Rich- ards 1954). The soil moistun^ percentage at 15 MPa, which is approximateK* equivalent to the wilting percentage, was 18%. These soils are thus relati\el\- fine textured on average. Sand, silt, and cla\' averaged 33%, 41%, and 26%, respectiveK'. Soluble Ca, Mg, and Na were 4.5, 2. 1, and 0.2 me(|/l, respectively (Table 1). Extractable (]a, Mg, and Na averaged about 431 1. 684, and 15 mg/kg, respectively. These con-e.sponded to 10.8, 5.7, and 0.065 meq/100 g soil luid exchangeable percentages of 23.8, 12.6, and 0.1, re.spec-tix'elv Thus, of the.se elements, (Ja wiis predominant on the exchange complex, and exchtuigeable Na was \ei"\' low. Howe\er, calcium was low relatixe to comparable sites of \egf4ation and landsc-ajx\s (Hansen, Hoffman, and l^jugstad 1984. Hansen and Hoffman 1988). Simple correlation coefficients for densitxol either chokechern' (r = .26 to -.18) or snow- berr\' (r = .36 to -.20) with various soil proper- ties were low (Table 2). TweKe soil properties were negatixcK associated with chokechera' d(^iisit\. Phosphoins showi^d the greatest posi- tive relationship with chokechern densitx (/" = .26). OnK four soil xariables (pH, P. extractable (>a, and (JEC) were negati\eK correlated with snowbern' densitv Magnesium showed the highest coriclation with snowbern densit\' (r = .36). Soil properties \aried some tor both spe- cies at the microsite le\el but were not statisti- calK different (/; < .10). For example, when densit\ ofchokechern w'iushigh (no snow bern), phosphonis was somewhat greater than phos- [)li()rus on sites with high snowbern densities (no chokecherpy), and thus, a positive correla- tion. St(>j)wi.se nmltiple regression using all soil properties with either chokecheny or snow- bern- stem densitx did not pnnide meaningful results. Howexer, a good relationship wa.s found 38 c;heat Basin Natuiulist [Volume 52 Taui.k 2. Simple correlation coefficients for densities of chokeclierr\- luid snowbi-ra witli chemical properties of soil of green ash/eliokeclierr\ habitat t\pe near liison. South Dakota (n = 72). Soil Chf)kechern Snowbern pll KC Orgiuiic matter NO:vN P K Zn Fe Mn c:u C.'a \a SAK Satn ration Ext.'Ca Ext. Mg Ext. Na CEC(meq/l(X)kg) 0.1 9° -O.Hi -0.17 -0.03 0.26° O.M -0.13 -0.11 -0.03 0.07 -O.IS ().]7 - 0.00 -O.OS -0.10 0.02 0.0] -0.13 0.04 -().20° 0.2S°° 0.15 0.10 O.Ofi O.IS 0.23" 0.03 0.23" 0.09 0.25" ()..3ft" 0.30" 0.08 0.10 -0.16 0.23" 0.17 -0.02 •Sinniricaiit ill a =0.5. °°Sij;niricaiil al a = .()l. Extrattahle cation tor [)ro(liclino; chokccliern den.sitrv using snow- hern' tlensih and cauopx' eo\er of grass (Table 3). Predicting snowheny stem density using choked lern densit\ and grass cover similarly showed a good relationshij) (r~ = .50). When snow'hern' stem density was high, chokecherry .stem densitv was low and \ice versa (Fig. 1). Chokecherrv densitv' showed a good relation- ship (r" = .48) with canopy co\'er of grass (Fig. 1 ). Stem densities of chok(^chenv were greatest when canop\ coxcr of grass was k)w\ Oxcrall. soil properties were not highK' corre- lated with either chokechern or snowbern' stem densits'. Each shrub was more infhienced by the densit\of the otheror the amount of grass co\er. Factors such as other shrubs, trees, dis- ease, fire, .soil compaction, and grazing ma\ also inlhience stem densit)'of"both chokechern and snowbertA (Boldt et al. f97(S, Se\erson and Boldt 1978, Uresk and Paintner f985, Uresk and Boldt 1986, Uresk 1987), but these factors were not considered in the present study. Summary Surface soils of the gnx-n ash/chokecheny woodland in northwestern South Dakota near Bison were found to be moderateh' fertile with CO z HI Q >- cr LU m O z 15 12 -♦ _ FITTED ■X ACTUAL ■* * ■ * +* ** * ** 1 . . 1 7r**^ 0 3 6 9 12 15 CHOKECHERRY DENSITY 15 W 12 LU Q >- 9 CC LU I O 6 LU o ^ 3 — FITTED * ACTUAL -\ * * * * \ c * * * ■ \. i - *s< * * . ♦--< * + ^\^ * * * ^s, >^* * * . * * ^< * ■ * "> s.- Ij_ 20 40 60 80 % GRASS COVER 100 Fig. 1. Snowheny stem densitv (stems/0. 1 \u~) is greatest wiien chokecherry stem densitv is the least, but decreases as chokechern densit\^ increases. CliokecheriA stem densitv is greatest wlien grass co\'er is the least, ami densih' decreases as grass ccner increases. fairh- high lexeLs of nutrients except phospho- rus, which was low, and nitrogen, which was uioderateK low. Organic matter ranged from about 47( to 20%. These soils were fine textured with UioderateK' high cation exchange capacitv' and saturation percentages. The\' were classed as non.saliue-nonalkaliiK^ with low amounts of exchangeable sodium. Soil jirojierties showed low correlation rela- tionships with chokechern' or snowbern stem densit\. A good relationship was found lietween the t^v() species of shrubs and grass. Additional factors such as d(^usit\ of other shrubs or trees, di.sease, lire, soil compaction, and grazing may also infhience densities of chokechern or snow- bern and interact with soil surface properties. 1992] Soil Chemistry and Plant Rklationsiiifs 39 Tahlk 3. Coefficients (a. b, aiul c), standard error of the estimate (SE), and correlation (r ) describing relationsbips of" cbokecherfN' (C), snowberrv (S), luid grass (C) in green ash/chokecherr\- habitat t\pe (n = 72). Densih(Y) SE r\pe Cliokt'c hern' 9.651 -().48SS -().().S2(; I.nundcrstor^■ Lod^ plants. 1'^ treatments on regeneration of ,u.t.v.woodIanck^ ,' ^ -, • V n Proxenza I T Flii clers. E. D. northern Great Plains. Praine Naturalist 18: 193-202. M^rt^ . c^ul s ^o icL Ji^vu-posuu^^ ..n Uu.sK. 1). W, and W W Pa.wtneh. 1985. Catde di.ts in a P i^ e bivoa'lr.teractions, 7-9 August 1985, Snow- ponderosa pine fojest in the --^^^^^^ "ills, bird. Utah. USDA Forest Senice Gener.J Technical Journal ol Range Management oS: 44(^2. lk'i-K)rt INT-222. Intermountain Forest and Range Exiwrimcnt Station, Ogden, Utah. 179 pp. Received 1 November 1991 Accepted 16 Jamianj 1992 (;R-at Basin NatiinJist 52^ 1 i. 1992, pp. 41-.52 THE GENUS AK/ST/D.A (GRAMINEAE) IN CALIFORNIA KclK \\. Allrcd' Arstuact. — Till' t;L\()iioi)i\ ol Aiistidd ( Crainiiicac ' in ( .'aliloniia is revised. Tlie liciiiis is ri'presented in tlie state 1)\ six species and 1 1 ta\a. Identification ke\s, descriptions, selected s\ non\ in\, dislrilmtion records, and illnstiations are prox ided. Kct/ uords: .\ristida. //()C/.s7/r.s, Ciilifonna. As part oltlu" current rexision of Willis L\"nn jepson's .\ Manual of the Flowerino; Plant.s of (-"alifornia ( 1923), ,spon,sorecl l>\the Jep,son Iler- hariuni ot the Unixersitvof California at Berke- le\. an (\\ainination of the taxononn, nouienclature, antUlistrihution of the California sp(^cie.s of Aristida was undertaken. Jepson ( 1 923) originalK li.sted 10 .species oi'Aiistida for California, and subsequent floristic endeaxors increased this number to 12, reported by Munz and Keck (196(S). This work treats si.x species ap[)orti()ned to 1 1 total ta.\a. Aristida are peculiar in the de\tdopnient ol the iusilonii, indurate floret. The lemma (in North .Ameiican species) is convolute iuid conipleteK' encloses the palea and flower, forming a rather firm anthoecinm. or flower casing. This configu- ration customariK prexents the exsertion of anthers and stigmas, resulting in cleistogamons (and st^lf-pollinated) reproduction. Howe\er, in souie spikelets of A. pmyurea Nuttall, A. diiaricata Humb. & Bonpl. ex Wilk^now, and other species, swelling of the lodicules will often spread the lemma and palea, and the antheis and stigi 1 uis are commoi \\\ e.x.serted from tl \v an tl k k'c- ium during and afteranthesis,e\idence of possible cros.s-pollination. In A. dicJiotonui Michaux of ceutnil and ea.steni United States, two kiiuls of flowers ai-e de\ eloped: one with three anthers each 2-3 nun k)ng, presumabK adapted for chasmogamous reproduction, and the other with a single anther less dian 0.3 mm long (j)ersonal ob.senation). The smaller anther is alwa\s found retainetlwithiu the floret and aj^paRMitK functions ill clcMstogamous n^production. I'his condition is LiLso reported for A. oli^aiUha Michaax (Uenrard 1929). The tip of the leuuna often bears a column or beaklike structure in species ol Aristida, and tw o terms describe this condition. An awii column is formed b\ the couni\ent or coalescent. often twistetl bases of the awns alxne the lemnui. This is a relati\el\ unconnuon arrangement but is seen in Aristida califoniica Thurber. A beak of the lemma, howexer, is sometimes formed b\ the lennna apex. It is often narrow and twisted, as in A. divaricata and A. pinyurca. The term (iwn. as used luM'ein, refers to the free portion onK and is measured from the summit of the beak or awni coluum to the tip ol the awn. North American Anstida have been classified in three different sections of the gemis: ArthradwrunL Sircptachnc, and Aristida (Chactaria) (Uenrard 1929, Cla\ton and Renxoi/.e 19Sfi). In section A/t/jraf/irn/;;;. the lennna bodx is terminated by an awn column that disartic-ulates from th(> rest of the floret. This section is represenletl in California by A. califoniica. The section Strcptacltnc is charac- terized b\- the extn^ne reduction of the lateral awns, illustrated consistently in A. ternipe.sCiXv- auill(\s. but also found in other species that are not usualK placcnl in this section, such as A. adsccnsioiiis Linnaeus. In a study of Amf/f/r/ species affiliated with A. divaricata, Trent (1985) found that some degree of reduction of the lateral awns was a couunon occurrence in numerous sjiecies, and concluded that this f(^a- Inrc was often not a good indicator of biologic relationship. The \alidit\ of the section Stn'ptachnc ba.sed on this criterion is doubtful. .Section Aristida comprises the remaining (Cali- fornia species without articulation in the lennna or consistent reduction of lateral awns. ' Dipartiiieiit ot Animal and Kange- Sciences. Bon .3-1. New Mexict) State University. 1-ls C:nKvs. New Mexic-o SS(K)3. 41 42 Great Basin Naturalist [Volume 52 Because the sectional classification of the genus remains lari^cly unexamined and imsatis- factorv', for this re[)ort the California species are sorted into informal "groups." These groups do not necessariK correspond to any formal rank hut parallel those used b\ Ilitclicock and (>hase (1951) and Allred (1986). Group ADSCENSIONES. — Ah.sfida ad.scen- sionis; characterized h\ the annual habit, branching at the upper nodes, and erect awns. Group DiciiOTOMAE. — Aristkla oligantha; characterized by the annual habit, branching at the upper nodes, and a tendency for the central awn to coil. Group DixakiCATAE. — Ahstkia d'waricata tmd A. temipes; chtiracterized by tlie stiffly spread- ing piiman' (and often secondary) bnmches wdth a\illan [)ul\ini. These two species are usuiJly placed in different sections of the genus (Aristkla and Streptachne, respectiveK). Group PurPUREAE. — Aristkla puiyitrea, including sexen \arieties; characterized by gen- eralK unecjnal glumes, a narrowed beak of the lenuna, and generally erect branches; merges with the Divaricatae through A. purpurea van parishii (Hitchcock) Allred, as well as A. pansa Wboton & Standle\'of the Chihuahuan Desert. ( ;h{ )U 1' Tu B !■: 1k;u LOS a E . — Arisi kla califor- iik-a; characterized by the disaiticulation of the awnis and awn column from the l)od\- of the lennua. Following are identification keys to till taxa, descriptions based on Cialifornia specimens, counties of occurrence in California, lists of selected specimens examined, and an illustra- tion of each taxon. Herbaria arc^ abbreviated according to Holmgren et al. (19(S1). Updated information on the distribution of Aristkla in Cialifoniia will be welcomed by the author. Aristkla Limiaeus, Sp. Pi. (S2. 1753. Tufted annuals or perennials; ailms generalK erect, the internodes mostly semisolid. Sheatlis open. Uiudes a ring of hairs. Blades flat to in\o lute, lacking auricles. Injlorescence generalK a panicle, occasionally racemose or spicate. Sj)ikclrts 1 -flowered, di.sarticulating above the glumes. Chinws etjual to \er\' unequal, thin, membranous, 1- to 7-nened, often as k)ng as the floret or longer. Lenuna 3-ner\'ed, terete, indurate at maturity and enveloping the palea and flower; eallus oblicjue, usuall)' sharp- jiointed and bearded; aicns 3 in number, termi- nal on the lenuna, the lateral awns sometimes reduced or obsolete. Falea 2-nerved, thin, shorter than the lemma. Lodicules 2. Stamens 1 or 3. Carijopsis enclosed in the anthoecium, hisiform, the hilum scar linear, the embryo .small. X= 11. Key to the Genus Aiistkld I . Culm internodes and nodes eonspicuously hairy A. califonuca var. califomica Cuhn internodes and nodes glabrous 2 2(1). Plants annual, generally much branched above the base 3 Plants perennial, simple or onl\ \\ eaklv branched above the base 4 3(2). Central awns mostly 3-7 cm long ... A. oligontJia Central awais mostly 0.7-2 cm long . A. adsccnsionis 4(2). Primary panicle branches erect to spreading or diooping, but at least the bases of the branches appressed to the main iixis, without pulvini in the branch axils A. ptiqnnva Prinii\r)' panicle branches abniptlv spreading from the main axis with pulvini in the branch axils ... 5 5(4). Lower panicle branches ascending, the upper branches appressed .... A. pinjjurca vm. pari.sliii Lower and upper panicle branches spreading ... 6 6(.5). Anthers O.S-l mm long; summit of lemma twisted at maturitv; base of blade glabrous abo\ ethe ligule A. dhurkdtd Anthers L2-^3 nun long; sunnnit of lemma not or onK slightK- twisted at maturity; base of bladewith scatteied pilose hairs above the ligule A. tcntipcs Aristida adscensionis Linnaeus, Sp. Pi. 82. 1753. Six weeks threeawn (Fig. 1) [A. adscenswnis var. ahortiva Beetle, A. adscen- sionis var. decolorata (Founiier) Beetle, A. adscensionis var. niodesta Hackel]. Tufted and generally annual, but e.xtremelv variable in size, growth habit, and longevit)'; culms erect to geniculate, simple to much-branched, (3)1()- 50(80) cm tall; internodes glabrous. Sheaths generally shorter than the internodes. Li^jides 0.4-1 nun long. Blades flat to involute, 2-14 cm long, 1-2.5 mm wide. Panicle narrow and con- tracted, 5-15(20) cm long, often internipted below, tlie spikelets aggregated on short branches. CUumes unequal, 1-nerved, the first 4-8 mm long, the second 6-11 mm long. Lcnufuis 6-9 mm long, slightly flattened, sca- brous on th(^ midneiAe; awns flattened at the base, .spreading, the central awii 7-18(23) mm long, the lateral awns somewhat shorter, rarely 0-2 mm long. Palea 0.5-1 mm long, hvaline, blunt, fan-shaped. Anthers 0.3-0.7 nuii long. Can/opsis somewhat shorter than the lenuna. 2)1 = 22. Diy, open places and rocky hills below 19921 GKNUS/\/i/.S7V/A\ IN CJ.M.IFOHMA 43 Fi>4. I. Ari^tida (uiscciisioiiis. inflorescence and spikelet. 1 ()()() 111. COUNTIKS: Imperial Inyo, Los Angeles, Hixerside, San Bernardino, San Diego, San Luis Obispo, Santa Barbara. Aristkla adscensionis ranges in liabit troin small, unbranched plants scarcely 3 cm tall with onK one or t\\T) spikelets to large, mnch- branclied clumps SO cm tall witli immerous branches and spikelets. Sexeral \arieties liaxc been named based on differences in plant and [xmicle size, degree of branching, and the devel- opment of the awns. N'ariation in size and robustness seems related to precipitation, and populations at the same site max \ an drasticall\' troni \('art()\ear. The\alidit\ ()l nnluced lat(M-al awns as a taxonomic character is also (jiiestion- able. Most species o{ Aristida haw forms with the lateral awns reduced, and this seems to occur almost indiscriminatek and without any correlation with other features. Selected specimens. — Imperial Co: rd from Ogillix to Bhthe, 17 Feb 1958, Bacigalupi, H. 6136 [|EPS]; Carriso Mts, Painted C;orge, 17 Mav 1938, Ferris, R. S. 9622 [UC]; near Dixie- land, 13 Oct 1912, Parish, S. B. 8239 [JEPSf Inyo Co: Panamint Mts, Deadi Valley, 18 Apr 1978, Dedecker4541 [UC]; 11 mi W of Death Valley, 28 Mar 1947, Keck, D. 5847 [UC]. Los Angeles Co: Pasafk'ua, 27 Feb 1882, Jones, M. E. s.n. [CMl; San Clemente Island, 8 Mav 1962, Raven, P M. 17609 lUC]. Riverside Co: 9.4 mi N of BK-the, 19 Feb 1958, Bacigalupi, R. 6188 [JEPS];' Marshall Canyon, 10 mi W of Coachella, 16 Apr 1905, Hall,' II. M. 5797 [UC]; near Mecca, 28 Jun 1902, Parish, S. B. 8122 [UCJ; S end of Coxcomb Mts, 27 Mar 1941. Wiggins, I. L. 966 [UC]. San Bernardino Co: NW side of Coi)per Basin, 6 Ma\ 1939, Alexan- der 710 [UC]; Sheep Mole Mts, 25 Apr 1932, Ferris, R. S. 8020 [UC]; Needles, 12 Mar 1919, Tidestrom, I. 8556 [UC]. San Diego Co: San Diego, 29 Apr 1902, Brandegee 832 [UC]; 6 mi NW of Agua Caliente, 5 Apr 1960. Everett 24075 [UC]; 1.5 mi E ofWillecitos, 28 Jan 1940, Munz, P A. 15856 [UC]; Borrego Springs, 18 Mar 1976, Schroeder 51 [UC]. San Luis Obispo Co: San Luis Obispo, 9 Ma\ 1882, Jones, M. E. 3245 [UC]. Santa Barbara Co: Santa Ynez Mts, 9 May 1954, Pollard [ UC]. Aristida californica Thurber in S. Watson, Bot. Calif 2:289. 1880. Tufted, slightly bush\ perennial; culms erect, much-branched, gener- all\- 10-40 cm tall; inicrnodes glabrous or pubes- cent. Sheaths much shorter than the intemodes, pubescent at the throat and on the collar. L/g- tdes about 0.5 mm long. Blades mo.stK' folded to in\ olute, occasionalK' flat, stiffly .spreading, 2-.5 cm long, inostK' less than 1 mm wide, scabrous to hispid-pnbenilent. Inflorescence few-flow- ered, 2-6 cm long, the terminal ones paniculate, the axillan- oiu\s racemose. Chimes unecjual, l-nen(Hl. Lenniia with a narrow column at the tip formed b\' the twisting and fusing of the awn bases; awns nearly ecjual, breaking from the lemma, the zone of articulation at the ba.se of the awn column. 2n = 22. var. californica. CxilFOHMA TIIKEPIWN (Fig. 2). Iittenuxh's pubescent, the hairs pilose to sublanose. Clluines \c\\ unequal, the first 4-8 mm louiiand the .second 9-12 mm Icmg. Lemma bod\ 5 7 mm long when mature, the awn coluum S 26 mm long; awns 2-4.5 cm long. Diy, sancK, desert areas. Coi'NTIES: Imperial, Riverside, San Bernardino, San Diego. The other \ariet\- of this species is \ar. olahrala \'ase\-, known principally at the species Ie\el as Aristida rata (Vasey) Hitchcock. This varietx- differs from \ar. caUfonuca primariK' in having glabrous, rather than pubescent, 44 (;hkat Basin Naturalist [\\)luine 52 inteniodes and octiu-s in die slighdy higher ele- sations oldie deserts to die east of the range of \ar. calijomica. Both taxa are cbploids {2n = 22), and the)- oxt-rlap considerably in spikelet dimensions (Keeder and P\dger 1989). Variety ^lahrata is not knowni from ('alifoniia. SELKCTLD SFECIMKNS. — Inipei-ial Co: Signal Mt, 2 Apr 1903, Abrams, Ci. D. s.n. [DS- ] 86664] [ DS]; 8 mi E of El Centro, among larrea bnshes. 22 Apr 1942, Beetle, A. A. 3172 [AllUC]; Bard, near Arizona line, 22 Sep 1912, Thornber, J. J. s.n. [ARIZ], a few mi E of Holt- xille, Jun 1951, Tofsrnd. H. s.n. [AHUC]. Riv- erside Co: nearTlionsand Palms, rockv desert slopes, 27 Apr 1943. Beetle, A. A. 1938 [AHUC]; Pinto Basin, 16 mi from Cottonwood Springs, 15 May 1938, Ferris, R. S. 9522 [DS]; canxons along Colorado River, 1 May 1905, Hall. H. M. 5963 [ARIZ, POM, UC]; Coachella \'alle\, 6 mi SE of Caniet Station, sand dunes, ca 500 ft, 1 1 Mar 1928, Howell, J. T. 3443 [DS, CAS, AHU(]]. San Bernardino Co: Joshua Tree National Monument, 1700 ft, north ledge, TIS RIOE, 18 May 1941, Cole, J. E. 734 [UC]; Baxter, S of Mojave River, 23 May 1915, Parish, S. B. 9886 [UC, DS]; Dale Lake Valley (W of lake), 13 mi E of 29 Palms, sun-dn' sand flats, abundant. 29 Max 1941, Wolf, C. B. 10876 [RSA, DS, CAS]. San Diej^o Co: San Felipe Narrows, ca 350 ft, 20 Apr 1935, Jepson, W. L. 17101 [J EPS]; canvon W of Borrego Spring, 1.500 ft. 19 Apr I9()6. jcmes, M. E. s.n. [POM- I 1 700 1 I 1 POM I; Colorado De.sert, clay hills, 25 jun 1SS8, Orcutt, C. R. 1486 [DS]. Aristida divaricata Ilumb. & Bonpl. ex W'illck'now, Enum. Pi. 1:99. 1809. PON'KKTY TiJKliEAWN (Fig. 3). Tufted perennials; ciihits erect, mo.stly unbranched, 25-70 cm tall; iiitcr- nodes glabrous. SJieatlis longer than the inter- nodes. iJffih's 0.5-1 mm long. Blades looscK inxolute, glabrous, 5-20 cm long, 1-2 mm wide. Fnniclc open, 10-30 cm long, 6-25 cm wide; priniaiy branches stifflx spreading from the main axis. axillanpuKini present, 2-12 cm long, generally naked on the lower portion. Brditch- lels and s))ikclct.s general!)- appressed along the branches, but .sometimes si)reading. Chimes nearl) etjual, l-ner\ed, 8-12 mm long, acumi- nate-aristate. Lemma (S-13 mm long to base of awns, the terminal 2-3 mm narrowed ami geii- erall) twisted fonror more turns; <'/u/j.s subecjual to une(jual, (7)10-22 mm long, the lateral awns at least slightl)- shorter than the central. Anthers 0.8- 1 nun long. 2n = 22. To be k)oked for on d\\ Ply;. 2. Ah.stiild ccdijontica, iiillorescenee, spikelt't, and ck'tail of hranchiiii';. slopes below 150 m elevation. COUNTIES: San Diego. It is doubtful that Arisiida divaricata cur- rently occurs in (>alifornia. Most reports are based on collections of C. R. Orcutt in 1884, and no knowni specimens haxe been collected from the state since that time. In addition, it is possi- ble that Orcutt's labels are in error, because on at least one specimen of A. divaricata he located Hansen's Ranch, which is in Raja California, in San Diego Countx'. A similar species, Aristi(hi orciiftiana N'asev, also supposetlK was collected from southern Calilornia in 1884 b\ (]. R. Orcutt, and hvo specimens are hou.sed at US. The labels (k'scribe San Diego as the collection 1ocalit\'. and these specimens are apparently the basis for reports ol either A. orctittiana or A. scJiiedeana Trinius & Ruprect from California (Abrams 1923, Jepson 1923, Hitchcock 1924, Munz & Keck 1968). Coincidentally, the t\pe locality of /\. orciitiiana is again Hansen's Ranch in Baja California, mentioned abo\e. It is possible that neither. A. divaricata nor A. orcitttiaiui was e\er collected from California b\- Orcutt, but from 19921 CiENUS/\/^/.S77/;.A IN C^ALIFOHNIA 45 Fi'j;. 3. :\risli(l(i diiaricafa. innoresceiicc. spikek't, and hasc ol i)laiit. Baja ( iaiitornia. Arisfida orciiUidna rcsciiibles A. (livdi'icald in tlit^ stiifl\ sprcadiiiu; panicle hranclu's, hnt the lateral awnis are \eiy short or absent, and the blades are cjeneralh' flat and somewhat cm ling in orcutfiaiui. Sl'i:(:iMi;\S KXAMINED. — Withont detiiiite loealitx but recorded as California: Santa ( ^ata- hna Mts [Santa Catalina Island?], in 18S4, Orcutt, C. H. 2 [US]; Santa Clara Mountains Ipo.ssibly Arizona?], in 1SS4, Orcntt, C. 1^ 2 |US[. San Diego Co: San Diego. Orcutt. C. H, s.n. |\Y, US]. Aristida oU'^iintha Michanx, Fl. Bor. Ainer. 1:41. ISO,). OLDFIELD TIIREKAWN (Fig. 4) |A. oli'j^tmllia \ar. nervata Real]. Tufted auuuals; culms win, 3()-7() cm tall, mucii-branclied, the iunoxations extraxaginal: iiifcniodcs glabrous, pith\. SJwatlis nio.stlv shorter than the inter- nodes. Ligules 0.1-0.5 mm long. Blades flat to in\ olute, 3-22 cm long, 1-2 mm wide, reduced Fig. 4. Ahstid/i olifiantliti. inllorL'scciici', spikclft, aiitl detail ol hraiK-liiii''. upwards. Injlorcsccncc few -flowered, race- mo.se, the spikcdets nearh' sessile. GliiDics sub- cHjual or the second longer, awn-tipped, most!) (12)18-34 nun long, the hrst 3- to 5(7)-neived and shoi-t-awTied, the second 1 - to 3-nened with an awn S-13 nun long. Lciniua (10)13-20 mm long to base of awns; cciitrdl (iwii (2)3.5-7 cm long, the lateral awns generally somewhat shortc-r. 2// = 22. Dn hills and fields, bare ground, scrub land, 90-1000 m elevation. C()L\Tli;S; .Vniador, Butte, El Dorado, Hvun- boldt. Imperial, Lake, Madera, Mendocino. Merced, Modoc, Nevada, Placer, Redding, Sac- ramento, San Joacjuin, Shasta, Siskiyou, Solano, Sonoma, Stanislaus, Tehama, Tuolumne, Yuba. 46 Great Basin Natuhai.ist [\ blunie 52 Some specimens of Arisfidn oJi]; Trinitv' River near mouth of Willow Creek. 15 Sep 1919, Tracv 5222 [UC]; vicinity of Carbenille, 27 Aug 1933, Tracy 13()()() [UC]'; Dobbyn Creek, 9 Juri934, Tracy 13341 [UC]. Lake Co: dn hills between Upper Lake and Scott \alle\-, 17 Aug 1905, Tracy, J. P. 2365 [UC] (\ar. nervata). Madera Co: Mintum, 1 Oct 1936, Hoover, R. F. 1618 [JEPS, UC]. Merced Co: Tuttle, 17 Jul 1936, Hoover, R. F. 1580 [JEPS, UC]. Modoe Co: 19 Aug 1935, Whitnex, L. 3627 [UC]; M(4cher Creek, 6 Sep 1935, Wheeler, L. C. 3959 [US] (\ar. nenata). Nevada Co: Talioe Natl Forest, S of Grass \ alley, Aug 1931, Smith 2638 [JEPS, UC]. Sac- ramento Co: 5 mi SE of Folsom, Yates, H. S. 5953 [UC]. Shasta Co: Redding, 21 Jun 1909, Blankinship [JEPS]; 1 mi N of Anderson, 21 Jul 1932, Long 190a [UC]. Stanislaus Co: vicinit\ of La Grange, 30 Sep 1961, Allen [JEPS]; bet\\'een Knight's Fern- and Wanienille, 1 Sep 1941, Hoover, R. K 5582 [UC]; 1 mi NW of Waterford, Yates, H. S. 6858 [UC]. Tehama Co: 9.7 mi N of Red Bluff, 14 .Aug 1954. Bac- igalupi. R. 4808 [JEPS]; \blcanic Plateau NE of Red Bluff, 22 Sep 1940, Hoover. R. R 4617 [UC]. Tuolumne Co: near Kevstone, Yates H.S.6148[UC]. Aristida purpurea Nuttall, Trans. Amer. Philos. Soc. 5:145. 1837. Tufted perennials; culim erect and general!)- unbranched, 10-80 cm tall; i)ifcnioclcs glabrous. Sheaths longer than the inteniodes. Li'. 419S 1 US|. Inyo Co: spc'ciuieu with- out lo(alit\ at KS.VPOM. Riverside Co: (.'huckawalla Spriugs, 15 uii SE of (luiladax, 9 ful 1957. Crauiptou. H. s.u. [AIIUCl; Palui (;auyou,4 Apr 191 7, johustou. 1. \1. 1008 [US. MI(>H]; Rix'crside aud \iciuit\ ol upper fork of Salt Creek Wash. 19 Mar 1927. Heed. E M. 5440 [AIIUC, HS.VPOM]: betweeu Marcli AEB aud Lake\iew.29 Apr 1966. Koos. ]. C. s.u. [RS.VPOMl. San Bernardino Co: 2 uii NE of Eifteeun-iile Poiut. 3()()() ft, 28 Apr 1935. Axelrod, D. 321 [AHUC, UC]; behveeu Bulliou aud Sheep Hole Mts. 7 Apr 1940, Muuz. P A. 16568 [RS.Vl^OMl; Budweiser Wash. u(^u-35d Fi'j;. 9. . \;-/.s7(r/c/ piiqiitrca \ ar. piiq)urc(i. iiilloivsctMice and S|likrl('t. 46ui X, 1 15d 44iu W, (;rauite Mts, 28 Oct 1977. Prigge, B. A. et al. 2320 [RS A/POM]. San Diego Co: 0.5 uii N of Mirauiar Resenoir cla\ soil. 4 Mar 1981, Re\e;J, ]. s.u. [AHUC]; Auza Cauvou E of juliau. 3 Apr 1940. W'ilsou. E. s.u. [AHUC]. var. purpurea. Pi Hl'LE THREEAWN (Fig. 9) [/\. })iir})iir(ii \ar. raJifornicn Vase\]. Culms 2.5- 60 ciu tall. Blades flat to iu\olute, uiostly cau- liue. .3-17 cui loug, 1-2 luui wide. Panicle puiplisli. often uoddiug. 10-25 cui loug. tlie brauches usualK delicate, droopiugor llexuous. Chimes uue(jual. the hrst 4-9 luui long, tiie second 7-16 uuu loug. Lemma 6-12 uiiu. 0.1- 0.3 luiu wide just below the awiis; aivns 2-3(4) CUI loug. 0.2-0..) uiin wide at the ba.se. '2n = 22. 44. 66. 88. DiA, gra.s.sy hills, scrublands. 2.5()-S()0 ui elexatiou. COUNTIE.S: Mono, Rixenside, San Bernardino, San Diego. This is a beautiful grass, with its droojiing. red- di.sh.plnnielike panicles. It conuuouly intergrades w ith the varietes m'allei/i, lon^seta, iuid wn<): road from High- land to Huiiniug Springs, 1 nil Irom valley floor, 26 Jun 1942, Beetle, B. A. 3644 [F, WIS]; near Upland, 7 Nov 1916. lohnston, I. M. 1120 iMICHj; San Bernardino N'allev, 2 jun 1906, Parish. S. B. 5783 [NMCR]; Clark Mts, 5 Aug 1950. Boos, j. C. et al. 4906 [BSA/I^OM, UC]. San Diego Co: 6 mi N of Ocean Side Ranch, coast hills in chaparral, 21 Apr 1942. Beetl(\ A. A. 3145 [TAES]; near Vallecitos Station, 2 Apr 1939, Gander, F 7142 [MICH]; Ilarhi.son C;an\T)n, 19 Jun 1938, C;ander, F F 5999 [BS.WOMl. van wrightii (Nash in Small) Allrcd, Brittonia 36:393. 1984. Whiciits thhki:a\\\ (Fig. 10) [A. wii'/.s/7/)\ i\ (:\i,ii-()1{\ia 51 Spikclcts oppressed or sprcadinsj; Iroiii the hranclu's. GliiDics about e(jual, l-nciAcd. 9-15 nun long. Lcinnia 10-15 mm long. nsnalK not twisted at the ape.\; aivns e(|nal to \ci\ nnc(|iial. Anthers 1.2-3 mm long. var. hamuloHii (llenrard) Trent, Sida 14(2):26(). 1990. HooKTllHKK WW (Fig. 1 1) [.A. hdinulosa llenrard, Med. Hijk.s Herb. Leiden .54:219. 1926]. Central awn 10-25 mm long. Ltifcral aicits mostly 6-23 mm long, .sometimes shorter. 2// = 44. Dw hills and slopes. lOO-SOO ni ele\ation. COUNTIK.S: Butte, Colusa, Fresno, (ilenn. Kern, Los Angeles, Madera, Kixerside. San Bernardino, San Diego, Santa Barbara. Sonoma, Stanislaus. Sutter. Tehama. Tulare. Wntura, Yolo. Trent and Allred (1990) doeumented the moiphologie \ariation and similarit\()LA/7.sf/r/c/ Irrnipcs and .A. Iianuilosa. eoneluding that tlu^ lunniilosa taxon should be treated as a \ariet\ ol fcrnipcs. \'ariet\' ternipcs does not oceur in Cal- iloniia and differs oiiK in the length of the lateial aw lis. \'ixnct\luniinli>s(i also resembles A. (lit tiricala. which diffeis most eonsistently in liaxing shorter anthers and lacking pilose hairs ab()\e the ligule. Based on numbers of speci- mens in California herbaria. \ar. hainulosd is unusualK' common. Selected specimens. — Butte Co: Soudi Butte, 10 Sep 1981, Ahart 1535 [UCJ; along lIwT 32, 1 mi E of Chico, 16 Aug 1983, Ahart. L. 4277 [TAES]. Colusa Co: 10 mi W of Wil- liams, 5 Jul 1955, Burcham, L. T. 317 [AllUC, TAES, UC]; 10.7 mi SE of Leesville, 19 May 1 958, Crampton, B. 4789 [AHUC]. Fresno Co: Citnis Grove, 11 May 1940, Hoover, K. F 4385 [UC]; 8 mi N of Orange Cove, 8 |nn 1960, Howell, J. T. 35481 [ISC]. Glenn Co: 5.5 mi S ofOrland, 29 May 1942. Beetle. A. A. etal. 3353 [AHUC]; 5 mi \\' of OHand on the XewAJllc road, 27 May 1914, Heller, A. A. 114.32 [US|. Kern Co: lowest slopes of the Tehachapi Mts. 15 mi S of Bakersheld. 14 Apr 1942. Beetle. A. A. .3017 [AHUCJ: 15 nn S of Bakersfiekl 7 |un 1946, Beede, A. A. 4679 [UC]. Lo.s Ange- les Co: Alta Dena, 2 Apr 1905. Grant 66-64.59 [ARIZ, BS.ATOM, UC]; Pomona, 1 Jul 1937. I lorton 448 [UC]; Li\eoak (^an\-on, San (iabriel Mts. 15 Apr 1934, Wheeler, L. C. 2525 [ A H UC | . Madera Co: near Raviiiond. on sheep lancli. II Nhiv 1934, Wikson.'E. s.n. [AHUC]. River- side Co: 10 mi N of Pala, 17 Way 1964. Hitch- cock. C. L. et al. 23113 [NY]; lower San Jacinto Rixer Canyon. Yates, H. S. 6710 [UC]. San Bernardino Co: near Upland. 7 Xo\ 1916, John.ston, I. 1121 [ARIZ]; nie.sa near Rialto. 20 May 1888, Parish, S. B. [UC]; Granite Nh)un- tains, Budwei.ser Wash, 28 Oct 1977. Prigg(\ B. A. et al. 2321 [RS.VPOM]. San Diego Co: Rolando. 14 |an 1938, Gander, F F 4936 [SD]; San [amento'. 4 [nl 1890. Hasse, H. E. s.n. [NY]; Escondido. 10 "Aug 1928, Meyer 652 [JEPSJ. Santa Barbara Co: Santa ('ni/ island. X of biological station in central \alley, 23 Apr 1979, Thorne. R. F et al. .52466 [RSA/POM]. Sonoma Co: Little CyeNsers, 1 mi E of Big Sulpliur Creek. 10 Aug 1984. Leitner [UC]. Stanislaus Co: \ icinitx of La Grange, 30 Sep 1961, Allen, P s.n. | AHUC, JEPS]. Sutter Co: Sutter Buttes. 10 Sep 1981, Ahart L. 3129 [NY]. Tehama Co: about 5 km N of Black Butte Resenoir and about 17 km N\\' ofOrland, 26 .Mar 1990. Buck. R. 1469 [JEPS]; Jelly's Fenv Rd. 0.5 mi from 1-5 exit. 16 Aug 1991. Allred K. \V. 5467 [NMCR|. Tulare Co: Three Rixers. 24 Aug 1905, Brandegee s.n. [UC]; 10 mi SE of Portenille on Tule Indian Resen'ation Rd, 28 Dec 1964, (;uthrie. L. 66 [AHUC]; Fountain Springs Rd. 6.3 mi W ol (California Hot Springs. 25 Jnn 1966. Twisselmann, E. C. 12537 [AHUC]. Ventura Co: Upper Santa Ana Creek, Santa Ynez footliills, 13 fun 1957. Pol- lard. H. M. s.n. [TAES]. Yolo Co:" foothills, open slope. 2 mi W ol Winters. 24 Aug 19-53. (^ramp- ton, B. 1600 [AHUC]. ACKNOW I.KDCMENTS I am grateful lo the Friends of the Jepson Ilerliarium. who proxided traxel funds for stuck in Caliloiiiia. to an anon\uious rexiewcM' lor a meticulous criti([ue, and to the curators of the foHowing herbaria for their hcdpful cooperation and n.se of plant materials: AHUC, ARIZ. DA\'. JEPS. RS.\/I^()M. TAES, UC, and US. Geoffivx Le\in of the San Diego Natural Histon Mu.seum })r()\ ided \aluable assistance by track- ing down pertinent collection information. Paul Peterson of the Smithsonian Institution and [ames P. Smith of Humboldt State Unixersity look time to locate specimens and information. and John W. Reeder and Richard Ledger ol the Unixcrsitx ol Arizona generously shared with mc^ before publication their obsenations on Aristida californica. The illustrations were expertK- rendered by Robert DeWitt Ley. Tliis is [oumal Article No. 1583. New .Mexico Agri- cultural Experiment Station. 52 (;hkat Basin N atuhalist [N'oli LiTKRATURK CiTKD AlJKAMS. L. 1923. Illustrated flora of the i^icific States. X'ol. I. Stanlord University Press, Stanford. California. Ali.KI;1). K. W. 19(S4. Morphologic \ariatioii and elassihta- tion of the North Auwrican Arislkla inirpiirca complex (Gramineae). Rrittonia 36; 382-395. . 1986. Studies in the Aii.stidfi ((Jraniineaei oi the southeasteni United States. I\' Ke\ and conspectus. Rhodora 88(855 ): 367-^387. Cl.ayton. W. D., and S. A. Hiwoizk 1986. (;enera graniinnni: grasses ol the world. Kew Bulletin Addi- tional Ser XIII. IIl".Mi\HD. J. T. 1929. .A monograph ot the genus Aristida. I. Mededeelingen \'an"s Rijks Ilerharinm Leiden .No. 58. Hitchcock. A. S. 1924. The North .American species of Ari.slkhi. (Jontrihutions of the United States National Herbarium 22:517-586. IllK M< i)( K .\. S.. and A ClI.ASK 1951. Mainial of the grasses of the United States. United States Depart- ment of .Agriculture MiscelKuieous Publication No. 200. HOLMCHKN. P K., W. KELKf'.N AND E. K. SCIIOFIFI.D 1981. Inde.x Herbariomm, Pt. I. Holm. Scheltema, and Holkema, Utrecht, Netherlands. |i;rs()\ W. L. 1923. A manual of the ilouering plants ot California. University of California Press, Berkelew .Ml :\/ P A., and D. D.' Kfck 1968. A CaHfornia flora. Uni\ersit\()t {California Press, Berkeley. 1681 pp. Rkkdkh J. li, and R. S. Fkl<;KH 1989. The Arislida ralifi>niic(i-^lahr(itfi complex i (Iramiiieae). Madrono 36;' 187-197. Thkn'I'. J. S. 1985. .A studv of moqihological variabilitv in divaricate Aristicia of the southwestern United States. Unpublished masters thesis. New Mexico State Uni- \ ersih. Las Cnices. 90 pp. Tlu;\T J. S., and K. \V. Allhkd 1990. A taxonomic com- parison oiAiisfida tcniipcs Cav. und Ari.stida luiinuhmi Ilenr Sida 14: 251-261. Rccriicd loMati njyi Rciisrd21 Jaiuian/ 1992 Accepted 1 Fehnian/ 1992 Cicat Basin Naturalist 52(1), 1992, pp. 53-5S TEMPERATURE-MEDIATED CHANGES IN SEED DORMANCY AND LIGHT REQUIREMENT FOR PENSTEMON FALMERI (SCROlTiULARI.ACEAE) StanlcN (;. Kittlu'ii aiul Susan K. McNcr Abstract. — Pciistciumt pdlmcri is a sli(irt-Ii\ccl prrcnnial Iit-rl) coloni/iiiii distmiu-d sites in sciiiiarid liahitats in iIr' western USA. In this stuck .seeil was liarxcsted lioni si.\ nati\e ami ionr seetled p()|)nlali()iis dnriniJ \\\o conseciitixe \c"ars. In lali(irat(>i\ t;einiination trials at eonstant 15 (', considerable between-lot \ariati()n in prinian' dormancy ;uid light icijuirenii-nt wasohsened. Fonrwet'ksol moist chilling ( 1 (-) indnccdsccondar\ilormanc\ at 15C. Cold-induced secondan' donnainA was rexersed 1)\ one wt-ek oltlark incubation at 30 C. This warm incubation treatment also reduced tlu' light requirement of unchilled. after-ripened seed. Fluctuations in dorinancN and light reijuirement ol buried seeds haw been linki'd to seasonal chtuiges in soil temperatin-e. Pcnstcinou palmcri germination responses to temperature ap[X"ar to be similar to those ol lacnltati\e winter annuals. Kiij words: seed 'ji'iin'uiatiou. P(diiur jxitstciuou. seed hduk. induced doiiiunuij. heardtoiiinir. Fenstemon palmeri. Seed dorniancx iiiechanisms function to ensure that germination i.s postponed until con- ditions are favorable tor seedling suiAi\al (Fenner 1985). The le\el ol donnanc\' of an imbibed seed is dependent upon its dormanc\' jc\ ("1 prior t( ) imbibition and on the enxironmen- tal conditions to which it has been exposed in the imbibed state (Bewley and Black 1982). C'hilling, es.sential for breaking dormancN' in seeds of nian\' temperate species, induces \aiA- inii decrees of secondan' dormanc\ in others iBaskin and Baskin 1985). Conxer.seK, warm temperatures increase and diminish dormanc\' in other species. These temperature-mediated changes in seed dormancy are related to tlie s(>ason in whicli seeds undergo germination and cmergenc(\ Thus, spring and fall germinators tend to ha\e opposite responses to chilling and warm-temperatures regimes. Poisteinon palmeri Gnw is a short-lixcd perennial lierb nati\e to the southern half of the Cireat Basin and adjoining regions of the west- em United States (Cronciuist et al. 1984). It occurs across a fairh' broad range in elexation (8(){)-275() m), colonizing n^latixch ojM'U. carK successional sites such as roadcuts and washes. Indixidual plants produce large (juautitics ol seed tliat remain \ial)le for several vears in stor- age (Stevens et al. 1981). Numerous popula- tions ha\"e been successtulK established through artificial seeding on a \ariet\' of sites outside its natixe range (Stexens and Monsen 1 988 ). This \ersatilit\' raises questions about the establishment strateg\' of this species. In this stud\ the effects of moist chilling and warm incubation on seetl germinabilits' were deter- mined under controlled laboratoiA' conditions. The results are suf licientK clear to permit spec- ulation about seedbed ecolog\ and ha\e led to the fieldwork necessan to confirm the conc-lu- sions drawn herein. In laborator\ trials on F. paluicri. Young and Exans (unpublished data. C.reat Basin Experi- mental Range, Ephraim, Utah) demon.strated tliat germination at a constant 15 C was not significantK lower than at an\- other constant or alternating temperature regime. Germination o\er a 28-da\- period was suppres.sed at mean temperatures Inflow 10 and abo\e 25 C. Allen and Me\(M- (1990) reported similar results in a stnd\ of three Penstemon .species and suggested the p()ssibilit\- of cold-induced secondaiy dor- iiiancx in P fxihiicri. Field sowing of this species is usualK ( allied out in late fall and is based on tlu^ assumption that acoid treatment is required to break dormancv (Stexens and Monsen 1988). ' IS. D<-partiiieiit oi Ai;rii iilture-. Kort-st St-niix-. IntirMiouiit.iiii Kcsi-artli Station. Slinib Stiencrs Uilxiraton., Provo. Ctali S4fi(l6. 53 54 GwEA'Y Basin Naturalist [\ oluiiie 52 Mktiiods Seed Ac([iiisiti()n Ripened seeds were harvested frf)ni nine poj)- nlations in 1986. Collections wen^ made from eight ot the original and one n(n\ population in 19S7 (Table 1). Four of the populations were from roadside seedings outside the native range of this species. The genetic origin of the aitifici;illy seeded populations is unknown. Eacli collection was clean(^d using standard tec-hni(|ues and stored in envelopes at 20 (' (room temp(^rattn'e). \'iabilit\ l^etermination An estimate of viahilitv for each 1986 collec- tion was obtained using a tetrazolium chloride (TZ) t(>st. Four replications of 25 seeds from each collection were imbibed overnight. Each .seed was pierced and placcnlin a \% TZ solution at room tempcM'ature for 24 liours. Embnos were then evaluated for xiabilitv using estab- lished procedures (Grabe 1970). Gibberellic acid (CiA,3) effectivelv' breaks dor- mancv in F. pal inch .seeds (Young and Evans, unpublished data. Great Basin Experimental Range, Epln-aim, Utah). Four replications of 25 seeds for each 1986 collection were imbibed in 250 mg L" (».*\.s. Germination temperature was a constant 15 G. Germination percentages, determined after 2 1 davs, showed no significant differences betwec^i TZ estimates of \iabilitv and genninalion percentages in GA.3. Hence, germination in (iA^ was the onlv measure of \ial)ilit\' en'.ploved with 1987 seixl. FAperiment I Experiment I was started on 1 |une 1987. -Mean time after harvest date was a])proximatelv nine months (Table 1). The experiment was designed to ck'termine the effect of thn^e teni- p(M-ature pretreatnients on germination of seed from the nine 1986 collections under two light regimes. Pretreatnients inchuk'd: (1) chilling for 28 days at 1 G, (2) incubation for 7 davs at .'^O G, (3) chilling lor 28 davs at 1 G followed bv incubation for 7 davs at .'30 G. and (4) no pre- treatnient. (termination temp(Matm-e and dura- tion following pretreatment was a constant 15 ( '. for 21 days. The light regimes were a 12-hr photoperiod and constant darkness. Each pretri'atment/light regime combination was replicated fovu" times for each of the nine collections. Replicates consisted of 25 seeds placed on top of two germination blotters in a 100 X 15-nnn petri dish. Blotters were moist- ened to saturation with deionized water. Experimental units assigned the same pretreat- ment and light regime were randomized in stacks of 10. .'\ blank dish (blotters but no seeds) was placed on top of each stack that would receive light, ensuring that all seeds would receive light throuiih the sides of the dish onlv. Litiht intensity inside the dishes was 25 microein.steins m" sec' PAR. Each stack was enck)sed in a plastic bag and looselv sealed with a nibber band to retain mois- ture and facilitate handling. Dniing pretreatment, stacks were placed in cardboard boxes, each of which was enclosed in an additional plastic bag. After pretreatment, stacks assigned the light regime were removed from their boxes and randomly arranged in the growth chamber directl)' beneath fluorescent lights. The remaining boxes were placed in the growth chamber and were not opened imtil the ei^.d of their germination period. Seeds with radicle extension >1 mm were counted as germinated. Experience wath this and other penstemon species has shovvni this to be a clear indicator of the initiation of seedlins development. A germination percentage was determined for each replicate (dish). Germina- tion percentages were arcsine transformed for statistical analvsis. Experimental results were subjected to analvsis of variance procedures appropriate to the completelv randomized design, l^ecanse of the collection X treatment interaction in the analvsis of variance, each col- k^ction and treatment was analvzed indepen- dentlv. Significant differences among treatment and colk^ction means were determined using the Stndent-Neuman-Keul (SXK) method. Experiment II \ second (^\p(.Miment was started on 14 Octo- ber 1987 using nine fresh (1987) collections (Table I ). Mean time from hanest was approx- imatcK one month. The objective was to deter- mine the ellec't of .30 (1 (imbibed' on prinian- dormancv and light recjuinMuent of fresh seed, 'fhe methods w(>re the same as those used in the first experiment w ith tluee exceptions: onlv one pretn^atment was used (30 C]), the length of the preticatment was 14 davs, and the length of germination v\as 28 davs. Light and dark con- trols (no warm incubation) were a warm incubation was much less effectixe in HMuoxing the light requirement when preceded b\ chilling. CTermination rate at 15 C was onl\' slightlv accelerated b\ chilling and warm incubation pretreatments (data not shown). Mean gcMiiii- nation for the light control treatment after se\(Mi da\s was 15%, indicating that most essentialK nondonnant seeds recpiired a considerable period of imbibition before germination was possible. Foiu' weeks of chilling and one week of warm incubation increascxl the piojjortion of seeds that germinated b\ da\ 7 to 24 and 28%, respecti\el\ . Howexer, a major fraction of the seeds still required more than one week of con- stant imbibition at 15 C to cerminate. Experiment II In the first experiment there was a slight trend in the more dormant lots for germination to be higher after warm incubation relatixe to the control. The second experiment was conducted to determine if warm incubation could break the priman- dormancv of fresh seeds. Contran to what was expected for fresh seed, onlv t\vo of the nine 1987 collections showed significant priman' dormancx' (Table 4). The increase in germination percentage following warm incubation was significant when com- pared to the nonincubat(>d light control for one of these collections. In the remaining collec- tions, neither the light control nor the light, warm-incubated germination percentages were significantK' different from total \iabilit\- esti- mates determincnl In germination in GA3. The xariation in dark germination was similar to that obser\'ed in the first experiment with after-ripened seed (Table 4). The effect of warm incubation on dark germination was not as clear as in the initial experiment. Germination of the warm-incubated secnls resulted in a mean net increase oxer iioiiinciibated, dark controls of onl\- 11%. Fotn-of the nin(> collections showed significant increases, whili' one showed a decR^i.se. Discussion Moist chilling for four weeks caused vaning degrees of secondan dormancy in P. palnwri seed collections. Incubation at 30 C clearl) 56 Gii MAT Basin Natl'ivxlist [\bliiiiie52 TaBI.K 2. CkM-mination response ofniiie after-ripc'iied collections of'/' jxihiwri seed to moist cliilliiiti; ( 1 (^ lor 2S days) and warm incnhation (30 C for 7 davs). Tlie germination period was for 21 days at a constant 15 ( .' witli a 12-hr photoperiod. Cermination in 250 mg L (lAr; was nsed as an estimate of total \ial)ilit\ lor cacli collection. Mean germination percentage' Pretreatment Collection (.'ontrol Browse yoa Li'cds S9a Zion 72a K.0I0I) Hoad 95a Utah Hill S9a Moimtain \\t )me S (Table 3). donnanc\(lnringchilling. This suggests tliat late Light sensitixitv can be altered b\ tempera- winter/eady spring germination of some seeds ture shifts during seed imbibition (Toole 1973, is likely. It is of littU^ surprise^ that recentK Franklin and Ta\lorson 1983). This ma\- be due emerged .seedlings wt>re foimd in /' jxibiwri to temperature effects on the production, populations in both spring and fall. Such destruction, or dark rexersion of pin tochrome. biuiodal germination patterns are txpical of tac- Temperature shifts mav al.so alter other factors ultatixe winter annuals (Ba.skin and Baskiu associated with plntochrome action, thus 1985) and would be selected for in uupredict- resulting in an increase or decrease in light able habitats where the best season for seedling seusitixitv. Hendricks and Tavlorson (1978) sug- .sur\i\al maxdiffer from year t()year(Sil\-ertown gested that temperature effects on plnto- 1984). Such germination patterns xxould also be chrome action in s(>eds max be due to changes adaptix-e for .species that colonize different kinds in membrane llniditx. It is iikelx that the effects of habitats xxith xaning degrees of threat from of tcMuperatiuc on light .sensitixitx in seeds are a fro.st and drought. Both .situations occm- xxithin r(\sult of mor(> than one process acting in concert, the range of /^ /W///t'n. A light recinirenient max Iielp (k'tennine (Tixen its small .seed .size (Pluminer et al. sc^ison of germination for buricnl /' jxilntcri 1968), alight requirement for germination of F. seeds. I labitatsxvith adecjiiatewintcr snowspn pahiicri is not .surprising (Fenner 1985). Th(> xide enough moi.stiu-e for .spring germination of lexel of actixe phx tochrome in dn- .seeds and, suriace seed. Long periods (8-16 xx'eeks) of 1992] Fi:\sti:m()\ rMMF.iu Sv.KD Ckhmiwtiox 57 T\ni I o. The cITcct of chilling (1 C; lor 2, and diilling followed In- warm iiniiliation on the ligiit r('(jnir(>nient of nine after-ripened collections of P. palnieri. Tlie germination temneratnre was 15 (]. Ciermination percentage'' Light Dark (loilection Control C^oiitrol IC 30 C 1 C/30 C 751. 17e 6S1) 13d 551) 24c- 77]i 34f 7()a 33b S7a 65ab S3a 38b 76a 46ab fila 35b 721. 34(1 Browse yoa Leeds 89a '/ions 72a Kololi H(ud 95a Utah Mill 89a Monnt.iiii 1 l( ime 88a MiTcnr ( 'an\ on 86a SaltCrei-kC. ui\on 58a N'el.o l^ooj) 75a Means .S2a 5(-;c oZd 45c Ux\ 37c 35e 49c 31c 41b 231) 54b 591) 42b (iv 26b .541) 12c He 4()c 27e 'Williin ..collrctio.i. inr.iiis l.ill.mfil In till- s.uuv U-ttc-r.iiv not siniiiliciilK dillrn-iit ..t tl.ry, lir, 1,a, I ,SNk Tahi.I-; 4. Friman tlormancv, light re<|nirement. and the effect of warm incnl.ation i 14 da\s at 30 (.') on tlu' germination I nine tresh collections of P. palnieri seed. The germination period was 28 da\s at 15 C. Light treatments reeeixcd a 12-hr ihotoperiod. (ierminatnon in GA3 (2.50 mg L' ) was nsed as a measnre of xial.ilitA for each collection. (termination percentage'' Control 30 C pretreatment Collection Light Dark Light Dark C.\.i Snow's CaiiNon 94a .')lli S5a 34l. 97a Browse 86a 25c SOa 53b 93a l.ceolorado Plateau is not \et sulficieut]\' detailed to permit precise paleoeu\ironmental reconstructions. However, preliminan' conclusions suggest a cooler, moister climatic regime during the late Wisconsin glacial and a mosaic of vegetation tvpes, such as grassland and shnibln conunnnities. unlike the present vegetation at tiie localities. Ki'ii uonl.s: Qudtcnuirij. Citlonulo PUiicau. iiiilirojuxls. \\ iscoiisin ijjdc'uil. CrautI ('(uii/oii. races. This paper discusses the results of a prehiiii- uan- stucK' of late Quateman" arthropod fossils from ca\e deposits and packrat unddens from southern Utah and northern Arizona. This Qua- teman data source has not been anal\"zed before from the Colorado Plateau, although the arid Southwest has been the focus of pale- oen\iroinuental studies for appro.ximateK* half a centuiA' (Antevs 1939). Arid climate, coupled with episodic fluctuating water tables, has [)ro\en detrimental to the preser\'ation of most exposed fossil remains. However, the same xeric conditions, when coupled with a stable rock shelter, pnnide a tmique situation — dn' preser- vation. Such xeric locations provide the preser- V ation of not ouK' pollen and plant niacrofossils, but also soft tissues and other usualK' degrad- able remains of animals (such as skin, hair, kera- tinous tissues, and dung; Wilson 1942). The studx of packrat middens in the Southwest has provick'd a reconstruction of the Wisconsin gla- cial biological conuuunities never before obsenablc in such detail (see various chapters in Hetancouil ct af 1990). Thus, an entirelvnew held of research has been opened, and it should [)rove valuable in understanding tlie latest Pleistocene. On cave deposits were (juickK discovcMcd to ])(' a warehouse of late Pleistocene information. C\psum Cave (near Las \egas, Nevada) and Rampart Cave (western (Trand Can\on. .Ari- zona) were the .scenes of the first paleoecologi- cal studies utilizing drv-preserved dung ol an extinct animal. Landermilk and Munz ( 19.34. 1938) found a wealth of information presened in the dung of extinct Shasta ground sloth [Nothrotlichops shastciisis). Later studies con- cerned witli dietaiT recon.stnictions expoimded on the data axailable from dung of extinct her- bivores, including Shasta ground sloth, mam- moth [Manuntitluis). Harringtons mountain goat {OrecDHiios liarhn^totii), and bison (Bison), among others (.\hutin et al. 1961. Hansen 1980. I3avis c-t al. 1984, Mead, O'Rourke, and Foppe 1986, .Mead, Agenbroad et al. 1986, Mead et al. 1987, Mead and Agenbroad 1989). Packrats iXccHoiiui: Hodentia; (dicetidae) build nests surrounded bv construction materi- als collected from within 30 to 100 m of the house. The construction components are pre- dominantK plant materials, but the packrat also collects small stones, skeletal remains, and dung. .Adding to the mattMnals procured by the packrat are various vertebrates and inverte- brates who live in the nest and waste pile as cornmen.sals. Periodic hou.se cleaning produces a vv aste pile of debris. Urination on the waste pile (a nudden) ultimately may cement the remains into a rock-hard deposit, encapsulating , Institute of Alpine Researcli. Box 4.50. University ofColorado. Boulder. (:oloraarch on a seri(^s of insect fossil asseml)lahihnahnan desert regions of west- em Texas and sonth central New Mexico (Elias I9.S7, Elias and \an Devender 1990, 1991). Elias (1990) also recently pnhlished the resnits of a taj^honomic stnd\ designed to reveal the sonrces and possible biases of insect exoskele- tons in packrat middens. Mkthoi:)S 1 .ocalities .Matrices Irom packrat micklens and cave sed- iments were washed or hand picked for arthro- pod and other animal and plant remains. Packrat midden and ca\e deposits from two caxc sites were analyzed from (irand Canyon National Park (GRCA), Coconino Conntv; Ari- zona; three packrat middens from Salt Creek, Canyonlands National Park (CANY), San jnan 19921 QUATKHWm Al'.TIIHOl'ODS, Coi.Oim^X) Pl.ATKM" 61 (]ounh; Utali; and three paekrat middens and one ca\'e de[)()sit tioiii tlie Kscalante Hi\er region ol Cdeii (.'aiixoii National Hecreation Area (GLCA), Kane County, Utah (Fig. 1 ). Bida Ca\e is a large limestone eaxc located in ])in\()n-jnniper woodland at 1430 ni ele\ati()n in CHCA. Cole (1990) reported on the paekrat niid(k'ns recovered from the ca\'e. Test pit e\ca- \ati()ns produced a multitude ol faunal and lloral remains (Mead 1983, OUourkeand Mead 1985, Mead, O'Rourke, and Foppe 1986, Mc\'iekar and Mead ms). Radiocarhon dat(\s (spanning from 2960 to 24,190 \t Bd'. ) on \ari- ous remains are presented in Mead (1983) and Mead, Martin et al. (1986); those ages from units containing arthropod remains are listed in Table 1. Kaetan Ca\e is a medium-sized limesttjue cawat 1430 m cdexation in GRCA. Mead ( 1983) e\ca\ated portions oi the deposit in tlie entrance room for the remains ol extinct moun- tain goat (Orcainnos Jiarhiif^^toiii) (O'Rourke and Mead 1985, Mead. O'Rourke, and Foppe 1986). Paleoenxironmental I'econstrnction l)as(^(l on the macrohotanical remains reco\(^red honi paekrat micklens and stratilied sediments is in manuscript (McV^ickarand Mead). Radio- carhon ages span the period from 14,220 to 30,600 vrB.R (Table 1). ThrcH^ paekrat luiddens selected from a series collected from Salt Creek Canyon, CANY (1505 to 1755 m elevation), have radiocarbon ages spanning 3830 to 27,660 yr B.R; toda)- the region is piuNon-juniper woodland with sage- brush Hats. Hie analysis of the maciobotanical remains and [)aleoen\iromueiital reconstruc- tions ol the middens is in man nsciipt (Mead and Agenbroad). Bechan C.dw contains copious remains ol extinct lied)i\()re dung ( Daxiset al. 1985, Mead, .\genbroad et al. 1986, Mead and Agenbroad 1989) recovered from floor .sediments dating I 1 .600 to 1 3.505 yr B.R Arthropods were recox - cred from tlu^ dung kucr and from an isolated ilolocene-age paekrat midden in the ca\e liable 1). Other nearl)\ [)ackrat middens con- tained additional arthropod remains dating Irom 1510 to 8640 vr B.R Insects Fossil insect sclerities were sorted from washed paekrat middens and ca\e sediment matrices. Robust specimens were mounted on modilied luicropaleontological cards with gum 'i"\ lii I I 1 „itc (,)u;itcTnai-\ deposits and ladicK-arhoii dates 1)111 sites on tlie (loiorado l^latean eontaininij artliropods. l.oealit\ 'Cane l>al) nnniher Ciiand Claiuon National Park, .Vri/.ona HidaCaw l.iver2 29(S() ' 200 .\-2836 L.a\vr 4 Hi, 150 r 600 HL- 11.35 l.a\cr .■) none — r>averS 24,190 + 4.3(X) 2800 .A-2.373 Kaetan ( -avc I,a\er i 1 1.220 - .■520 .•\-28.'3.5 Laser,". IT,.!!)!) + .'jOO .'\-272.3 I^a\ci" 3 none — l,a\er fi .■30.600 ± 1800 .\-2722 I,a\erS + none — I'aekrat niid( len 11) 17.100 - .500 .\-2719 Owl Hoost 1^2 21.430 i 1.5(X) A-;3082 0 none — Canyonlaiuls National Park, I tali Salt (Ireek (.'an\on i paekrat miildens) Head ( )\\l 1 A 38:30 ± 70 lieta- 18267 Woodenslioe 1 6980 ± 120 Bcta-27214 Hoodoo 1 27,660 ± .•340 Beta-27213 Glen Can>«)n National Hecreation .Vrea, I tali Ksealante Ki\cT region i paekrat nnddens) 13eehan ( :a\c 3 1510 ± 60 Beta-2.-3706 C;o\v-Perfeet 1 1820 ± 100 Beta-2;371 1 Bow lis 1 8640 ± 140 Beta-2.3704 Beelian Caw 15S 1 1.600-13..505 »Mshnilu,\:,lM .■I A..,nl,i„a,l M • a...iK/i-cl on MatHinuthiis (TiiaiiinKilli i ami cf. EuccratUcr- «■<• i)a\iM-t,il, 19S.5. Mead. .\<;ciilm)ail .-I .il. 19S(i, Me.ul tragacauth. a water-soluble glue. Fragile sp(>ci- meus and dnplicates wvvv stored in \ials of alcoliol. Fossils wcrv identified chiefl\- through comparisons with modern identified specimens in the U.S. National Museinu of Natural Iliston (Siuithsonian institution). Washington, D.C>. Some sjK'cimens were referred to taxoiiomic specialists, as noted in the acknowl(Hlgments. Mod(Mn ecological re(|uirements and distribu- tions for species identified in the fossil assem- blag(\s were comj)iled from the literature and from s])ecimen labels in the U.S. National Museum. All s|)ecinients will be curated in the National I'ark Service Repositorx, Laboratoiyof (,)naternar\ Paleontolog\-, Quatemaiy Studies l^rogram. Norihern .Arizona Unixersih. Results The fossil assemblages \ielded 57 identified taxa of insects, arachnids, and millipedes, including 15 taxa taken to the .species level. Table 2 shows the taxa identified from the 62 Great Basin Natuhai,ist [Volume 52 Tahi.F. 2. Fossil arthropods klciitificd from Rida and k'aetmi caves. GRCA. Arizona, in miiiinniin number of indi\idu;Js per sample. Rida Ca\e Kaetan Cave Taxon 2" 4 5 S l'' 5 S ()RR2' ()R2'' 11." colkoi'tkka Cakabidai-: Cahmwui cf. scnttator Fal). 1 — — — — — — — — — Aoonuni (Hlui(liiie) pcrlciis (.'sy. 2 — — — — — — — — — Afi^oiiiiiii {Rh(icliiis nr. nijicldrus Fail — — — 1 — — — — — — Aplioiliiis sp. — — — 1 — — — — — — OntliopJiOfius sp. — — — 1 — — — — — — Serial sp. 1 — — — — 1 — 2 1 — Phi/ll(>j)li(i^a sp. — — 1 — — — — 1 — — Diplotdxis sp. 1 — — — — — — 1 — — (^enus indeterminate 1 — — — — 1 — 1 — — Sii.l'iiii:)AF. Thdiuttopliilus tntn(tiiu\ Sav 1 — — — — — — — — — PriMDAK Ptinis ap. — — — — — — — 1 — — Nipttt-s cf, ventrirulns LeC, — — — — 10 1 — 9 — 4 NlTIDUl.lOAE Genus indeterminate — — — — — 1 — — — — Dk.kmkstidak Genus indeterminate — — 1 — 1 — — 1 — — HiSTKKIDAi: Ck^nus indeterminate — 1 — — — — — — — — El.,\TERID AK Genus indeterminate — — — — 1 — — — — — Tf-nkbriomdaF': Eleocles cf. ni^rina LeC, — — — — 1 — — 4 — — Eleodcs spp. 1 1 1 — 14 2 4 11 Coniontis sp, — — — — — 1 — — — — Mkloidai. Genus indeterminate — — — 1 — — — — — — Mki.andhyidak Auaspis nifd Sa\ — — — 1 — — — — — — ClIHYSOMEI.IOAK Ia'hui trilined White — — — — — 1 — — — — Chdetocncmd sp, 1 — — — — — — — — — Genus indeterminate — — — — 1 — — — — — Clf.ridak Acantlioscelidcs sp. — — — — — — — 1 — — CURCULIOMDAK Sapotcs sp, — — 1 — — — — — — — Oplin/dstcs sp, — 2 — 1 — — — — — — Scijphophonts dcupunctatus C,\]\. 211 — — — — — — — Orinuxlciiw protrartd Horn 1 — — — — — — — — — Clcoiiklius triiittdttis or C (jiiddriliiu'dtits — 1 1 — — — — — — — Apleums an<:,ul(iri.'i (IjL'C) — 1 — — — — — — — — Genus indeterminate — 111 — — — — Sc:OLYTIDAF, Genus indeterminate — — — 1 — Nkukoptf.ha MVRMFl.ON-riDAF Genus indeterminate — — — — 1 HOMOI'TFRA ClCADIDAE Genus indeterminate — — — 1 Hf.miftf.ha Genus indeterminate — — — 1 19921 Quaternary Arthhofods, Coioi^mx) Pi.atkmj 63 Tahi.k 2 covriMED. T;l\()ii Bida Cave Kaetaii Cave 4 5 S S ORR2' ()H2'' Okthoptkra ackididae Germs indeterniinate Lkpidoptf.ra (»enu.s indeti'rniiiiatc I I'l MF.NOI'TKHA Apoidea Genus indeterminate DlPTKHA Geims indeterminate Abac ii\ II) \ ACAHI IXOUIDAK Dcnnaccutor mulcrsoiii Stiles Dcrmaccntor sp. scohpiomda Bv:tiiidae Centtiroides sp. DiPLOPODA Genus indeterminate 'Niimliers refer to laver numbers at Bida Cave- NiiinlxTS refer to la\er numbers at Kaetan Cave. 'Owl Ran\on region, and Table 3 lists taxa identified from Glen Canyon. The assemblages are dominated hv taxa still foimd todax in the American Southwest, but many of the Pleistocene assemblages contain species that Ii\e toda\- at elevations higher than the fossil localities. As in other packrat midden and ca\e assemblages from the American Southwest, the fossil faunas are dominated b\' a few families of insects and arachnids. The beetle (Coleoptera) families (;aral)idae (ground beetles), Curculi- onidae (wee\ils), Ptinidae (spider beetles), Scarabaeidae (dung beetles and chafers), and Tenebrionidae (darkling beetles) were repre- sented in most assemblages. A few packrat and other mammalian parasites were found, includ- ing a tick (Ixodidae) and a blood-sucking bug (Rediniidae) that are knowni to parasitize packrats in their nests. A number of the identi- fied species merit indixidual discussion. Discussion of Selected Species The ground beetles from the fossil assem- blages include both ca\e dwellers and open- ground species. Th(^ cateipiHar hunter, CalosoDia scndaton was found in a late Holocene assemblage from the Grand Canvon (Table 2). This beetle is widespread in the United States, southern Canada, and northeni Mexico (Gidaspow 1959). It has been collected from the floor of Havasu (^ainon, GRCA (Ehas, unpublished data). The ca\e beetle. A^omni perlcvis (Fig. 2A), pre\'s on other arthropods. It is relatively coimiion in caws and near the mouths of mammal burrows. It is found toda\' from the state of Chihuahua, Mexico, northwest to southcni .Arizona (Barr 19S2). This species, found in Iat(^ Holocene asseml)lages in both tlie GLCA and (tHCA regions, was identilicd from Holocene packrat middens from sites in th(^ (>hihuahuan desert region of Mexico (Elias and \'au Devender. unpublished data). Another groimd beetle from the kite Holocene record at CtLC'A is Disrodcrus inipolrus. which Hxcs in open countiA'. It is common throughout the American Southwest and is found in the Chihuahuan, Sonoran, and Mojave deserts. The checkered beetle (Cleridae), Cynmioclcra pallida (Fig. 2E), is a predator of bark beetles in coniferous forests in the ('hiricaiiua, Rincon, and Huachuca mountains of .Arizona, as well as in mountainous regions of (Chihuahua. .Mexico (Wiurie 1952). C. pallida was found in a late Pleistocene sample from tlu^ (irand (]an\on. The dung beetle (Scarabaeidae), Aphodius nificlanis. was found in a late Pleistocene 64 Great Basin Natuhalist [\< olunie oz Tablk 3. Fossil arthropods idcntiUcd from the Cainoiilaiids and Clcn Caiixon region, Utah, in miniinnni ninnh(>r of indixiduals per sample. Taxon CANY' DOl.A' WSl HDl COLKOl'TKUA C.\KAI5ID.\K A}i,onum (Rltadiiic) pcrlevis (Isy. — Aiiwra sp. — Dlsaxlcnis inipotciis LeC. — Ciemis et sp. indeterminate — S(.ak.\b.^kii).m: Apliodius spp. — Atdcnius sp. — Scrira sp. — Mcloloiillia sp — Diplotdxis sp. — Genus et sp. indctciininatc — Ptinioak Niptus sp. 10 Ptiiiiis spp. — El.vikkioai: Genus et sp. indeterminate — BVKHIIIUAK C^enus et sp. indeterminate — TF.NKBKIOMDAK Eleodcs spp. — Couiontis sp. — Genus et sp. jniletcnninate 1 Di:hmi:stii)ak (k^mis et sp. intieteiniiiiatc' 1 ClIKVSOMKLIDAF. Altica sp. — PachtjhnicJiis sp. — (n^nus et sp. indeterminate — Cl.KKIDAK Ctjinatodcrd pdUuld Sehlir — IIOMOPTF.HA Rh.ni VIIDAK Tridtomd sp. — Lki'idoptf.ka Geinis et sp. indeterminate — MVMKNOI'TKH \ FOKMICIDAK ' Forinicd sii. I glc:a'' HC.r' C-IM Bl BC;i.5S 0 9 ■"CANY = Cany<)i)l;imls National Park. ''GLCA = C;leii C.'anvon National Uecrcalion Area 'Sites in Caiivoiilamls are: DOl A. Dead ()«1 1 A; W .SI . WikkUh ''sites in Clen Canyon are: B(:.3. Beclian Cave .^: C PI Cm-Pii »■ 1: HDl, lie; (I 1. HI Hour 1: H( 1")S. Beeli.mCave 1,5S. asscml)laL!;(' from (;IX>.\. This hectic lix'cs lodax throughout much ol western North .America from Saskatchew au iu the north to New Mexico, Arizona, and Clahiornia in the south. At the southern limit of its range, it liws in iiionntain- ous regions. The carrion beetle (Sil[)hidae), Tliaiialophilii.s tntitcaftis (Fig. 2B), lives in die southwestern U.S. and northern Mexico in habitats spanning altitudinal gradients from grasslands and arid scmb desert through oak-piinon-juniper wood- lands, pine forests, and montane meadows (Peck and Kaulbars 19S7). T. truiiaitus was loimd onK in a late Ilolocene assemblage from the (irand (lauNon. The spider beetle (Ptinidae), Niptus ventric- iiliis. is a scaxcnger that ranges from Texas west- ward to C'alilornia and south through Mexico to C»natemala. it probabK breeds in rodent nests. Modern specimens lia\t' been collected from packrat nests and from the fur of kangaroo rats, Di))()(l()i>u/s spp. ( Brown 1939, Papp 1962). This beetU^ speeic^s was common in sexeral assem- blaties from GLCJA. 19921 Qr ATKKNARY AUTI IH()I'()i:)S. COLORADO Pl.ATKAU 65 Fig. 2. SciUining electron iiiicrographs of fossil beetles from sites discussed in text: A, liead capsule, prouotuni, and eKtra of Aar e(|uals I nun. The ilarkliiiij; beetle (Teiiebrionidae). Elcodes ni^^riiui (Fig. 2C), was fountl in a late Pleistoc-ene a.sseiiiblage (roni tlu^ (tL(>.\. Tliis -scaxenger i,s known todax from tlie Pacilie Northwest sontli t(j the nionntains oi Aiizona. It is a eold-harcK species, foinicl at eknations iij) to 3050 HI in the Colorado Rockies (Blaisdell 1909). The false darklin'j; beetle (M(^landi-\idaei, Anaspis nija (Fig. 21)), is \\ides[)read toda\. Beetles in this faniik are fonnd nnck-r bark, in fun- plionis acnpiincfatits. Oninodcina pfoiracla. Aplcnni.s (iii^^iddhs. and Clconidiiis triiattalus orC. cjiiadriliiicattts. all Irom the ( irand (.'anxon assemblage. Of the.se, O. protracfa was lound onK in the late Ilolocene, A. au<^idaris and C Irivilfaliis or (.'. (pi(idnli)icaliis were found onl\ in the late Pleistocene, and S. acu))Uiirfaius was i(l(Mitified (rom both periods. O. protracta li\es at elevations from 2250 to 2700 m in the moun- tains of .\ri/.ona. It is a soil dwellcM- that feeds on loots (K. S. Anderson. National .\Insenm ot Natural Sei(Mices, Ottawa, written comimmica- tion. |nl\ 1990). A. aii^idaiis. C. tiiviHaliis. and C. (piadriliiicatiis are all widespread toda\ throughout western North America, while S. (iciipttiiclatii.s has been collected from Arizona and Mexico, where it feeds on A eastern Cl^C'A packrat mickleus (kMuoustrat(\s tliat individual plant taxaaiid comparable couiiiiiiiiities shifted upward appro\imat(4v 800 m at the close of the Wisconsin glacial (ca 11, 000 yr B.R). Cole (1990) concludes that the climate at the eleva- tions of Bida and Kaetan caves was nion^ conti- nental during the late glacial. This result is in contradiction to the equable climates that may have occurred in western and low(M--ele\ ation regions of the CRCA and to (he south of the Colorado i^lateau (Mead and PhiJlip.s 1981, VanDexender 1990). Our arthropod data pre- .sented here do little to clarify the continental \ s. equable climatic reconstruction contradiction. Our "cooler, moister climatic regime" recon- struction could be interpreted as a continental climate; however, it couklalso represent a n^ginu' with slightly cooler winters and cool sunnners. and therefore more available moisture. ACKNOWLEDCMENTS The scarab beetle, Aphodius ruficlanis, was identified by Robert Gordon, U.S. Department of Agriculture and U.S. National Museum, Washington, D.C. The weevils, Sct/pJioplwnis aciipiiiwtatiis. Oriinodcnui protracta, Cleo- nidiiis trivittatiis or C. cjuadrilineatus. and Apleiinis aiifi^idaris. were identified bv Robert Anderson, National Museum of Natural Sci- ence, Ottawa. The tick, Dernuicenforandersoni, was identified bv James Keirans, National Insti- tutes of Health, Bethesda, Mankind. We appre- ciate the help of Emilee Mead, Paul Martin, Bob Euler, and Bill Peachy. Scanning electron micrographs of insect fossils were taken with the assistance of James Nishi and Paul Carrara, U.S. Geological Sunev, Denver. Emilee Mead drafted the figures. Financial support for this studv was provided bv National Science Foun- dation grants EAR 8708287 and 8845217 to Mead and Agenbroad, and National Park Ser- vice contract CX-12()0-4-A062 to Agenbroad. Thanks are also extended to the staff at Ralph M. Bilby Research Center, Northern Arizona Universitx', for their support. Literature Cited A\TF,\ s, E. 1939. Stiulifs on the past climate in relation to man in the Southwest. C-aniegie Institution of Wash- in.j;t()n Year Book 38: 317^319. B\i;Pi T. C 19S2. The cavemicolous anchomemine beetles of Mexico (Coleoptera: Carahidae: Agonini). Texas Memorial Bulletin 28: 161-192. Bi-Twcoi HT j. L.. T R. \'a\ Devemm-h and R S. Mahtix 1990. Packrat middens. The last 4().()()()\ears ol iiiotic change. Uni\ersit\ of Arizona Press, Tucson. 4«7 pp. BiAlsDKij, E E. 1909. A monographic rc\lsion of the C;olcoptcra belonging to the Tenebrionidae tribe Ele- odiini inhabiting the United States, lower California, and adjacent islands. Bulletin of the United States National Mu.semu 63: 1-524. BH()\\\ W. j. 19.39. Niptiis Boil-Id. and allied genera in Norlli Vniciica ((.'olcoptcra: Ptinidae). Canadian Entomologist 91: 627-6.33. Coi.i: K. !,. 1990. Rate (,)uatcrnaiA \egetation gratlients through the (wand Canxon. Pages 240-2.58 in J. L. iiitancomt. I". R \an Dexcndcr, and P. S. Martin, eds., Packnit middens. The last 40.000 vears of biotic cliani^c. Uni\i'rsit\ (il .\i'i/,ona i'ress, Tucson. 467 pp. !>\\ IS (). K.. L. 1). .ACKXHHOAIX P. S. MaKTIN. AND |. 1. Ml.Al) 1984. The Pleistocene dung blanket of Bechmi (;a\c, Utah. Pages 267-282 in H. H. Genowavs and .M. R. Dawson, eds., ("oTitributions in Quaternan" ver- tebrate paleontologN : a \()lume in memorial of |ohn E. Cuilday. 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Extinction of Harrington's mountain goat. Proceedings of the National ,\cademv of Science S.3: S.36-8.39. Ml \l) J. L.M.K.ORoi KKE andT. M.FoPI'E 1986. Dung and diet ol the extinct Ihu-rington's mountain goat {OndimiDs liiiniii'^toiii). Journal of Mammalogv 67: 284-293. -Mk\I) J. 1.. \\l)A. M. Pi 1 1 1, 1, IPS 1981. The late Pleistocene and I lolocene fauna and flora of A'ulture Cave, Crand (.'anxon, Arizona. S()utln\esteni Naturtilist 26: 257- 288.' O'RniHKK M. k.. \\i) J. I. Ml \i) 1985. Late Pleistocene and I lolocene pollen records from txvo caves in the CIrand Canvon of .Arizona. USA. Pages 169-185 in B. Jacobs, P. Fall, and (). Davis, eds., Pleist(K-ene and Holoceue vegetation and climate of the southwestern Uuitet! States. .American .Associate of Stratigraphic Pa- Knologists P\)undation Special ("ontribution Series 16. P\l'l' C. S. 1962. .An illustrated and tlescriptive cat;Jogue of the Ptinidae of .North ,America. Deutsche Entomolo- gische Zeitscluift 9: .367-423. PE( K S. B.. \\n M. M. K\i i h\hs 19S7. A s\ nopsis of the distribution and bionomics of the carrion beetles (Col- eoptera: Silphidae) of the conterminous United States. Proceedings ot the Entomological Societv ol Ontario 118: 47-8 i. \'an Devendeh T R. 1990. Late ynaternai-\ vegetation and climate ot the Sonorau Desert, Unitetl States and Mexico, Pages 134-165, /(( J, L, Betancourt, T, R. \'an Deveuder. and P, S, Martin, eds,. Packrat nnddens.Tlie last 40.000 vcars of biotic change. Universitvol .Arizona Press. Tucson. 167 pp. \"al HIE P. 19.52. The c-hcn'kered beetles of north central Mexico (Coleoptera. (^Icridae). .AmericaTi Museum Novitatc>s 1.597: I-)7. \\iis()\ R. W. 1942. PreliminaiA stndv of the fauna of Rampart ( ^avc, Arizona, ("outributions to Paleontolog\-. Carnegie Institution ot Washington Publication 5.30: 169-1S.5. Rvci'ivcd 20 jiiiw imi Accepted 14 Idiiiian/ 1992 Great Basin Naturalist 52( 1 ). 1992. pp. (iS-74 MICROIIABITAT SELECTION BY THE JOHNNY DARTER, ETHEOSTOMA NIGRUM RAFINESQUE, IN A \WOMING STREAM Hohcrt A. Lcidy' Absth.u:!". — .Vlicroliahitat sek'ction b\- the johniiN darter (Ethcostotim uignun) w'-dv, examined in die North Laramie Ri\er, Platte (xnmtw WXoming. where it does not oeenr with odier darter speeies in die same stream reaeh. Eleetixity indices based on microhahitat ohsenations iniheate diat K. iiin avoids riffles and selects certain mierohahitats characterized by intermediate water depths in [lools and slow-m()\insi; nnis with a snbstrate composed piimaiilv ot silt and sand. Niche lireadth and electi\it\ \alnes for total deptli. bottom water \(locit\. and snbstrate measnrements from this shidv indicate tliat E. nif^niin is a habitat generahst. except at the extreme endsol the liabi tat gradient. Habitat use here is generajlv similar to other studies where E. nii^niin occurred with one or more otiier darter species. This stnd\ found little e\idence for competitive release in the absence ot other dartirs. Ki'ij words: microli/ihitat use. I'crcidiic. tiichc hrcadth. coinpditirc release, electicities. inoqiliohxj^iedl sju-euilizafions, Etlieostonia iiisinnH. Tlir joliiiiiN darter c.xliiliit.s the lafgest geo- graphic distnhution among the Noith Aineiicaii darters (Etheostomatini: Percidae), with the possible exception of Pcrchui capnxh's. It occurs farther west than an\ other darter except Ethcosfoiiia exile ( l^age 1 983). Tlie ecologv^ of E. nigniDi has ix^ceived consideral)Ie study, often in conjunction with other darter species (e.g., Winn 1958, Smart and Gee 1979, Paine et al. 1982, p:nglert and Seghers 1983, Mimdahl and Ingersol]'l983, Martin 1984). Tiie aliiiit)- of E. nigni)n to colonize such a large geographic area may he explained in part I)v its tolerance of a varietx' of emironmental conditions (Scott and Grossman 1973, Trantman 1981, Becker 1983). Throughout most of its range, E. /H'gn///i coex- ists with one or more darter species in streams (McCJormick and .Aspinwall 1983, Schlosserand Toth 1984, Todd and Stewart 1985). E. iiioimt)', Wyoiuing, drains the central .Medicine Bow Mountains and is a tributan t)f the Laramie Rixer, which in turn joins the North Platte Rix'er near the town of Wheatland. The stud\- was confined to a lOO-m reach of ii\er approximately 10 km upstream from Interstate^ Highwa\ 25 (ele- \ation 1420 m). .At this location the ri\er tra\erses a broad floodplain a\eraging().75-1.0kiu in widtli. Dominant oxenstoiA' ripaiian \egetation includes Cottonwood (Pojniliis dehoides) and \arious tree and shrub willows (SV/Z/.v spp.). The stucK area is U.S. Kiiuronmenlal Pr(>tci.tii>ii .Ay.-iicv. WVllands S.clion (\\-7-2). 75 I hiwllionic Slnct, Sail Kiaiici.scu, Caliloinia 94105. 68 19921 ETHF.OSTOMAMCIH M H AKINKSOI K in a WYOMIXC STIUvWI 69 s])ai"S('l\ populated \\ itli lai"25-5() nun); 4, large graxel (>5()-75 nnn); 5, small cobble (>75-150 mm); 6, medium cobble (> 150-225 mm): 7. large cobble (>225-300 mm); 8. small boulder 0300-900 mm); and 9. large boulder/bedrock (>9()() nnn). A cover rating (0-2) as measured b\ the relatixe degree of protection offish from stream \ elocit\', \isual isolation, and light reduc- tion (i.e.. shading) was assigned to each obser- vation. A rating of 0 denoted no protection; 1. moderate protectic^n; and 2, major protection. The general ty|3e and location of co\ cr in rela- tion to fish also wcm'c noted. Habitat a\"ailal)ilit\ was ck'terniined randoiiiK each dav innnecliat(d\ following the collection of microliabitat-u.se data (Mcnie and Baltz 1985). The lollowingavailabilitN' measurements were made along 10 ranck)ml\' selected tran- sects within the stuck reach: total depth; bottom, mean w ater cohnnn. and snriace \eloc- ities; substrate compcxsition: and co\er t\pe. Between 15 and 30 ecjualK' .spaced measure- ments were made along each transect. To ade- (|uatel\- characterize habitat a\ailal)ilit)- within tlie c()iiiparati\cl\ short stucK" reach, an effort was made to collect a[)[)r()>dmately t\\ice as iiiaii\ measurements of habitat axailabilitA' as microhabitat obseivations. .\n electi\it\ index was used to determine selectiv it\ In E. ni10-20 >20-30 >30-40 >40-50 >50-60 >60-70 >70-80 /^ Total Depth (cm) Fig. 1 A. Hclatiw t'recjucncv distributions of microhahitat nsv ami a\;ulal)ilit\- for total water roliiimi tk^pths lor E ni'^niin in the Xortii Laramie River. Eleeti\ities are indicated ++ (>().5(). strong preference), + (>0.25 lint <().5(). moderate preference). {) ( +0.25. no preference), - (>-0.()5 hut < -0.25,. moderate a\-oidance), and = (<-0.()5, strong avoidance). u c 0) 3 a> B 0.8 - •i 0.2- ■ Habitat Use m Habitat Availability .^ i/ ^ i^ 0-5 >5-10 >10-1S Bottom Water Velocity (cm/sec) >15-20 Fig. IB. Relative frequency distrihntions of microhahitat use and a\ailal)ilit\ for bottom water velocities for K. tlie Nortli I^iramie Rixcr. Klectivities are indicated ++ (>0.5(), strong pn-ierencel. + (>0.25 hut <().50. preference), 0 ( +0.25. no |)reference), - (> -0.05 but <-- 0.25, moderate avoidancii. and = (<-(). 05, strong aM in;^nini in motlerate in the .stream eiiNiroiuuent. Tlii.s iiide.x i.s based test for goodness of fit wa.s applied to freqnencv on the fonnula by Jacobs (1974), as modified b\- di.stributions lor habitat use and a\ailabilit\ to Moxle and Bait/. (1985) for detc>rminino; determine whether ma.ximnm differences niicrohabitat .selectivity- from variables .similar to between the obsent-d and expected distribn- thosensedin thisstndv .A KolmotioroN-.Smirnov tions were simiiheant (Sokal and !\ohll' 1981). 19921 ErUEOSTOM.WlClUM HAI'IM'.SgUE IN A WVOMINC; STIUvWI 71 0.8 n ■ Habitat Use m Habitat Availability 0 ( ( . r y ' / / } C Substrate Codes P'ig. KJ. Ht'lathc frecjueiicA clistrihiitioiis of niicrohahitat use ami a\ailal)ilit\ loi' substrate codes for ¥,. iii^niin in tlie Noitli Laramie Ri\er. ElectKities are indicated ++ {>0.50, strong preference), + (>0.25 but <0.5(), moderate preference), 0 (+0.25, no preference), - (>-0.05bnt <-().25, moderate avoidtmce), and = (<-0.05, strong avoichuice). An additional measure of microliahitat utiliza- tion, niche breadth, wa.s cakulated for E. nir a substrate of sand or small graxt'I, usualK in pools and slow-mo\ing nms of intermediate de])th (Table 1. F'igs. lA-C). In contrast, surface xclocitic^s often were rela- ti\el\- high. In tills stiuK. obsen ations Indlcatetl that indi- vidual fish wt>re positioned ( 1 ) on the surface of the exposed substrate with no apparent co\er, (2) immediateK below the front edge of a slight depression in the sand that .sened to protect fish from the current, or (3) rarely on the dowii- streani slope of a small cobble also protected from the current. In all cases, E. nignim (;he.'\t Basin Naturalist [Volume 52 T.Mii.K 1. Means (± S.D.) from iiiicroliahitat use and aviiilahilitv measurements lor E. nifinini in tlie North Lara- mie Ri\er, Wyoming. Habitat use Habitat \'arial)le obsenations availability Total depth (cm) 40.5 i 8.S 27.1 = 16,8 Focal point e\alnati(jn (cm) 0.1 i 0.01 — Relative depth (cm) 0.9 ± 0.02 — Mean water cohunn velocity (cm/s) 2.6 ± 4.5 3.7 ± 6.4 Focal point/ix)ttom \elocit\ (cm/s) 0.2 ± 0.7 1.8 ± 3.1 Surface velocit) (cm/s) 5.2 ± 7.3 5.4 ± 8.2 Substrate t\pes (%) (1) fines 62.1 T 35.8 34.1 ± 36.3 (2) sniiill gra\-el 16.5 i 19.6 21.6 ± 25.6 (3) medium gravel 7.6 ± 14.7 6.4 ± 13.3 (4) large gra\el 4.7 ± 13.5 5.8 ± 14.9 (5) small cohhle 6.3 ± 15.7 9.7 ± 21.5 (6) medium cot)l)Ie 2.1 ± 11.3 15.5 ± 28.7 (7) large cohhle 0.7 ± 0.20 6.5 ± 21.5 (8) small houlder — — (9) large houlder — — Cover code (()-2) Stream \elocit\- ] .5 ± 0.6 — \'isu;il isolation 0.5 ± 0.6 — Light reduction 0.1 - 0.3 — Sample size 9! 1(>S 'HfrerloMelliods T.\BI,k2. Niclic breadth values (/^',\aiid FTi lor E. iiip-iiin for total depth, bottom water velocitv. and substrate in the Nc)rth Laramie River, W'voming (approximate 95% conli- dcTice interval shown in parentheses). Bottom Total (l( ■j)th velocitv Substrate Hurlbert's B' \ ,45(,n. ,49) ,76 (,72, ,80) ,70 (,66, ,74) Sniilh's /• r .72 1,65, ,7S ,89 1,84, ,93) ,9.) (,89, ,96) positioned itself in close proxiniit)' with other t\pes of instream cover (e.g., stones, cobbles, branches, or small depressions in the sand). The average distance to such cover was less than 6 cm for 89% of the observations. Measurements of microhabital a\ailal)ilit\ indicatc^d that average water depths a\ ailable to E. ni<:^nini \v(M-e shallo\\'(>r than the depths at which it was topically observed (Kohnogorov- Smirnov te.st, .23, p < .01), and available mean bottom water velocities were greater than where fish were ol)seived(K-S t(\st, .25,/; < .01; Figs. ] A, B). In addition, available sul)strate was dominated by fines and small gravel (55%), but this was disproportionatelv low when compared with microhabitat use obsenations for these same substrate t\pes (79%; K-S test, .28, /; < .01; Fig. IC). ' Habitat Selection and Niche Breadth Electivitv indices indicate that E. nigrum was selecting certain microhabitats while avoiding others. E. nigami selected intermediate water depths and avoided high mean water column velocities (Figs. lA, B). There w^as a strong selectivity for a substrate composed of sand, and an avoidance of medium to large cobbles (Fig. IC). Fish generally avoided areas that ( 1 ) exhib- ited high surface water velocities, (2) were iso- lated visually, or (3) were well shaded by physical cover (Table 1). Rather, fish utilized relatively barren substrates exposed to full sun- light but close to cover. Microhabitat niche breadths (6'.\ and FT values) for depth, v elocit\', and substrate indicate little resource specializa- tion b)- E. nignnu (Table 2). Discussion The results of the electivitv indices and the K-S test indicate that E. iure obseiAcd were negligible when compared t()\(4(R ities at the same location a few centime- ters higher in the water column or at the surface. .Mso, subtle (Kpressions in the sand sub.strate olteii were occupied In indi\idual fish presum- ably for protection from stream \elocit\. One might expect that the small size and ob.sened patterns of habitat utilization b\ E. iuhe\enne. IfiS pp. I5i;< kii; (;. (,'. 19.59. Distribution ol central W'iseonsin fishes. Wisconsin Acadenn ol Science, .Arts, and Let- ters 4S: 6.5-102. . 19S.3. Fishes olW'isconsin. Uni\ersit\ ol Wis- consin Press. Maiiison. HoM.i; K, D.. and H. T. .Mll.lioi SK 197S. Hydranlic simu- lation in instream How studies: theor\ and techni(|ne. U.S. Fish and Wildlile .Seivice Biolosjical .Serxitvs Pro- gram FWS/()ISS-7.S/:5;3. (;()()X T. (;. 19S2. Coexistence in a "jnild oflK-nthic stream fishes: the effects of'tiistnrhance. Unpublished doctoral dissertation. University of C;alilbniia. Da\is. 191 pp. FxcLKirr J..aud B. II. Si:(aiRi{S. 198.3. Habitat segregation 1)\ stream darters (Pisces: Percidae) in the Thames River watershed ol southwestern Ontario. (Canadian Field Naturalist 97: 1 77-180. 74 Ghi:at Basin Naturalist [\ blume 52 Jac:obs, J. 1974. Quantitative meiusurenient of food selec- tion: a niodifkation of the forage ratio and Ivlev's eleeti\itv index. Oeeologia 14: 413—417. K.\HH. J. R. 1963. .\ge. growth, and food hahit.s ol johnny, slenderhead. and l)Iack.si(le darters oi Boone (lounts, Iowa. Proceedings of the Iowa AcadcniN <>( Science 70: 228-236. KkkBS. C. J. 1989. Ecological melhodolog). Ilatpcr and Row, Publishers, New York. 6.54 pp. L\(:il\KH, E. A., E. F. Westlake, and R S. Handwerk. 1950. Studies on the I)iolog\ of some percid fishes from western PennsxKania. .\inerican Nlidland Naturalist 43:92-111. M.MrriN. D. J. 1984. Diets of four sympatric species of Etheostoma (Pi.sces: Percidae) from southern Indituia: interspecific and intraspecific nniltiple comparisons. Environmental Biolog\- of Fi.shes 11: 11.3-120. M.ATTllFWS, W I., J. R. Bkk, and E. SUR.vr 1982. Compar- ative ecology- of the darters Etheostoma poclosteinoiic, E. flahcllarc and Pcrcina nmnoka in the upper Roanoke f\i\er drainage, N'irginia. (Jopeia 4: 80.5-814. McCoKMKk K II., and N. A.si'in\\'all 1983. Habitat selection in three species of darters. Environmental Biologv of Fishes 8: 279-282. MoYi.K, R B., and D. M. B.altz 1985. Microhabitat use bv an assemblage of California stream fishes: developing criteria for instream flow determinations. Transactions of the Aiiiencan Fisheries Societv 114: 69.5—704. .\Ii \i)\iii. \. D.. and C. G. iNGF.HSOi.L. 1983. Earlv autumn movements iuid densities of johnnv (Etiu'ostoiiui lu^ntin) and fantail (E. flahcllarc) tlarters in a southwestern Ohio stream, [onnial of Science 8.'3: 10.3^1 OS. Pack L. M. 1983. The handbook of darters. T F II. Publications, Neptune City, New Jersey. 271 pp. Pack E. M., and D. L. Swokfohd 1984. Morphological correlates of ecological specialization in darters. Envi- romnental Bif)log\()f Fishes 11: 1.39-1.59. Pain'k .\I. D.. |. j. DousoN. iuid C. Power. 1982. Habitat and food resource partitioning among four species of tlarters (Percidae: Ethco.stoimi) in a .southern Ontario stream. Canadian Journal of Zoolog)' 60: 163.5-1641. Sciii.ossKH I. J., and L. A. ToTll 1984. Niche relationships ami population ecologv of rainbow {Etheostoiria cacntlcnm) and fantail (E.flabcllare) diuters in a tem- poralK variable environment. Oikos 42: 229-2.38. SctriT. \V. B., luid E. J. Cr()S,sman 197.3. Freshwater fishes of Canada. Bulletin of the Fisheries Research Board of Canada 1984.966 pp. Smart H. J.,andJ. H.Cek 1979. Coexistence and resource partitioning in two species of darters (Percidae), EthcostoDw nigrum and Pcrcina maculata. Canadian Journal of Zoology .57: 2061-2071. SoKAL, R. R., and F.' J. Roiilf 1981. Biometiy W". H. Freemiui, San Francisco. Todd, S. C, iuid K. W. Stewart 1985. Food habits and diet;uA overlap of nongame insectiv orous fishes in Flint Creek, Okkdioma, a western Oziu'k foothills stream. Great Basin Naturalist 45: 721-733. Traitman, M. B. 1981. The fishes of Ohio. Rev ed. Ohio State University Press, Columbus. 782 pp. White. M. M.,andN. Aspinwall. 1984. Habitat partition- ing among five species of darters (Percidae: Etlicosfomii). In: D. Ct. Lindtjuist and L. M. Page, eds.. Environmental biologv ol darters. \\. Junk Publishers, Netherlands. Winn, H. E. 19.58. Comparative reproductive behavior and ecologv of foiuteen species of darters (Pisces — Per- cidae). Ecological Mongraphs 28: 15.5-191. Received 1 October 1990 Revised 1 May 1991 Accepted 1 October 1991 Creat Basin Natmalist 52( 1 ), 1992, pp. 75-77 NOMENCLATURAL INNOVATIONS IN INTERMOUNTMX llOSIDAE Arthur Croiuiuist 1,2 \hs IH \c:'l'.-New ta\a include Ijniiuliuin juiikurdidc (j'oikj. (Apiat-cai'). Crotoit tcxciisls (Klotzscli ' Mucll. Ar". \ar utiilicitsis (joncj. I KupliorbiafiMf' Other noinenclatnral innox ations inelnde: Cyntoptcnts longipcs v;ir. ibapensis (M. E. Jones) (aonij.. I.Diiiatiinn nisraniini (.'i()n(j. (Apiaceae); ('(iiiiissoiiia hootltii (Douglas) Haven vm: dccorticans (Hook. & Am.) Croncj., C/iinis.snniti hootltii (Douglas) Ra\en \m: (Iciri-tonnit iMunz) Croiiq., Caini.ssonid chivaefonni.s (Torr. & Frem.) Raven \ar. aurantiaca (Munz) Cronq., Cdinissoiiia cliiKicfoniiis (Ton: & Freni.) Ha\en \ar cnicifoniii.s (Kellogg) Cronq., Cami.s.soitia chivaefonni.s (Torr. & Frem.) Ra\cn \ar fniicrcd i Raven" (joiki . ('ainissonid clavaeformis (Torr & P^rem.) Raven var lancifolia (A. A. Heller) Cronq., Ctiinissonid lictcrocliroiiKi \S. WatsJ Raxcn \ar inoiioeiisus (Munz) (.'ronij., CamLssonia kcnicnsis (Munz) Ra\en viu. gilmanii (Munz) Croncj.. C.(i]iiissoiii(i sciqioidfn (Torr & Cray) Raven \'ar macrocai-jui (Rawn) Cronq., Oenothera Inennis L. var strigfisa (Rvdl). ) Cronq., Oeiiolheid pallida I.indi. \ar nnieinata (Engelm.) Cron(]. (Onagraeeae). Kci/ irords: nciiicnclatnrc. Rosida(\ taxoiiouui. M\ iiianiisc'ri[)t on a nunihcr ot tamilifs ol Hosidae for Iiitermountain P'lora has been com- pleted and awtiiting pul)lieation for .sexeral \ (nirs. These famihes should constitute a large part of \olunie 3A (Rosidae except Fabales). Since I cannot now anticipate when \olunie 3A \\ ill be published, the followino; nonienclatural inno\ations are liere \alidated. Apiaceae Ctjmopteriis longipes S. Wats. var. ibapen- siH (M. E. Jones) Cronq., conil). nov. [based on: Cijmoptcnis ihapci}sis \l. E. Jones, Zoe 3: 302. 1893]. Lotruitium packardiae Cronq., sp. now (Fig. 1). Ilerba ptM'ennia caespitosa radice crasse et caudice nianifeste ranioso, omnino sulnelutina, foliis omnibus Ixisalibus. teniato (\el quinato)-pinnatifidaet dcuuo plus-niinus\e pinnatifidis, .segmentis ultimis augustis, 1-2 nun latis. iiiiparibus, eis majoribus 1-3 cm longis; scapi maturi 1.5-4 dm alta, umbella ])rr anthesin compacta, pana, ca 2 cm lata, ladiis imparibus, demum aperta radiis longioribus 4-fi cm longis, bracteis inxolucelli panels, lineari- attenuatis \el nullis; flores flaxi, lobis caKcis minutis \('l obsoletis; pedicelli fructiferi 3-7 nun longi: nuMicaipia glabra \el interdum patenti-hirtella, S-9 X ,'3-3.5 nmi. maiiilcste alata, alis uscjue ad 1 mm latis. HOLXrrvrE. — Packard 74-46. in ash (hat has not disintegrated into clax. along Old Succor Creek Rcjad, near Sheaxille, \ev\- close to the Idaho border, T27S, H46K, Malheur Co., Oregon, 19 Ma\ 1974; NV! I.sot\pe at ClC Habitat and distrihutiox. — bi volcanic ash and rhyolite on rock\ cla\' soil in the sage- brush zone. Malheur and Lake cos.. Oregon, S to \\'ashoe and Humboldt cos., Nexada. Flow- ering from April to )un(>. COMMENTAR')'. — Lo null ill m packardiae has .sometimes passed in the herbarium as L. tritcniattiiii (Pursch) Coulter & H().s(\ which howcNcr has solitan or few stems or .scapes on tlie sinij)l(' or occasionalK' few-l)ranched crown or short caudex atop the taproot. The ultimate segments of the leaxes of/,, packardiae are also shorter than is tvpical lor L. triteniaiiim. the larger ones ouK 1-3 cm long, so that the lea\es haxc a dillercnt aspect. Lomatium roHeanum Cronq., noni. nox. Lepiotaenia leiher^ii (>()ulter 6c Hose, Contrib. U.S. Natl. Herb. 7: 202. 1900. Not Lomatium liihen'ii(.\m\[vybc Ho.se, 1900. ,The New York Botanical Clarde "Deceiised March 22. 1992. Bronx, New York 1(M.5S-.5126. 76 Ghka'i" Basin Naturalist [Volume 52 Fig. ]. I .ouKil'nnn juickind'u, Euimi{)HI5iakc:eae Croton texensis (Klotzsch) Muell. Arg. var. utahensis Cronq., \ar. lun-. A var. texeiisis loliis supra glahris diffcit. HOLOTVPK. — Cwntjuist 6 K. Thonic 11839. sand dunes ca 1pes at BRY!, UTC:! Co\IMl-:\TAKV.— Crofo/j tcxciisis is \ariahle in densit\()t ])ul)escence, hut tlir()u>i;houl most of its ran^e the upper surface ol the lea\es has at least a few stellate hairs (though these- ma\ eventnalK- fall off). An ahuudant population on the sand dunes nc^u- lAnnd\l in |ual) and Mil- lard COS., Utah, n-pre.sents the least pubescent extreme. In these plants the upp(>r surface of th(> Iea\es is wliolly glabrous or proxided willi ouK a lew (|uickly (k'ciduous stellate scales. The L\nindyl plants and some .similar ones from Kane and San Juan cos., Utah, and from northern Coconino Co. in Arizona, are here considered to form the \ ar. titahciisis Cronq. The othen\i.se fairly widespread var. texensis, with the upper surface of the leaves evidently (and more or less persistentlv) stellate-hain', is largely allopatric with \'ar. ufdhcnsis, bareK' entering Utah in San Juan Co. Ona(;raceae Camissonia boothii (Douglas) Raven var. decorticans (Hook. & Ai-n.) Cronq., comb. no\. [based on: Gaurd dccoi'ticans Hook. &Arn. Bot. Beechevs Vo\age343. 1S39]. CamisHonia boothii (Douglas) Raven var. desertorum (Munz) Cronq., stat. nox. [based on: Oenothera dccoiiicans \ar. (h'sciit)niin Munz, Bot. Gaz. 85: 246. 192S|. Camissonia clavaeformis (Toit. & Frem.) Raven var. aurantiaca (Munz) Cronq., stat. no\-. [basetl on: Ocnothcni scdpoidca \ar. aunintiaca S. Wats. Proc. Amer. Acad. Arts 8: 595, 613. 1873; an illegitimate name which as defined by Watson included the t\pe of the earlier O. scapoidea xar. clavaeformis S. W^its. 1871. Oeiiotliera clavaeformis \'ar. aurantiaca Munz, Amer. J. Bot. 15:237. 1928]. CflmissomV/ clavaeformis (Ton*. & Frem.) Raven var. crucifonnis (Kellogg) Cronq., stat. nov. [based on: Oenothera cniciformis Kel- logg, Proc. Calif. Acad. Sci. 2: 227. 1863]. Camissonia clavaeformis (Torr. & Frem.) Raven var. fmierea (Raven) Cronq., stat. no\. [based on: Oenothera clavaejormis subsp. fu)H'rea flaxen. Uni\. Calif Pub." Bot. 34: 106. 1962]. Camissonia clavaeformis (Toit. & Frem.) Raven var. lancifolia (A. A. Heller) Cronq., stat. nov. [ba.sed on: Clu/lismia lancifolia \. A. Heller. Muhlenbergia 2:"226. 1906].' Camissonia heterochroma (S. Wats.) Raven var. monoensis (Munz) Cronq., stat. now [based on: Oenotlwra heterochroma \ar. )iionoeiisis Mnn/, Aliso 2: 84. 1949]. Ckimissonia kernensis (Munz) Raven var. ^ilmanii (Munz) Cronq., stat. now [based on: Oenodicra dentata \ar. caif)iis Schedl. 195S; Ci/clorhipidion diJiinisiniin kn Xtjlchorm diJungensis Schedl, 1951; HijpotJicnemus (itcrriimilus for Lcpiccroi/lcs (now Hi/pothcucniu.s) (itcrhiuiis Schedl, 1957; Hypofliciiciiiit.s khinliitskiiyac for Hypotluncinus iiisnlnri'^ Kn\()lutska\a: Piti/ophthoni.s nfricdiiiilits {'or NaHlnjococics (now Pityoplithonis) (ifricaiiiis Schedl, 1962; ScohjtogeiKs /)(//)(/(//,s;,s for \iil()cn/i)tii\ (now ScDlijto^enes) papiKinus Sclicnll, 1975; Scolytogcncs panuloxiis for Scolyt()<:,cii('s paptiauiis SL\\ri]\. \'>n't>:\iililHiniui\\pi)iipi>slinis (or Eidopliclus (now Xylel)(»iiiti.s) spiuipciinis Schedl, 1979; Xi/lebonis fonno.sac for Xi/lchonis foniuisdtiiis Browne, 19.S1. New combinations for fossil Scolvtidae include Dnjocoetes diliaidlis for Pifi/oplitlwmidcd diliniiilis Wickliam, 1916. and Hi/lcsiniis liydropicus for Apidnccp1i(dus hydmpictis W'ickham, 1916, Phlocotiihtis ziiiniuTintmui Wickliam, 1916. is transferred to the famiK C'nrculionidae. In Scolvtidae, Crypludiipliilu.\ Schedl. 1970. is a junior generic sviionvm oi Sail ijt a ^c lies Eichhoff; Mdcrocn/phidiis Nohuchi. 19S1. is a junior generic s\non\ni o( tli/pnthciicimis Westwood, 1836; Ni})poiiopolt/<^raphiis Nohuchi, 19S1, is a junior generic s\nonvm o'i Pohi'^niphiis Erichson, 1S36; Pseiidocosinodercs Nobuchi, 1981, is a junior generic .svnonym of Cosiiiodere.s Eichhoff, 1878; 'I'dpiiwcocfcs Pfeffer, 1987, is a junior generic synonym of Tc//;/(/v)/-)/r/i!/.s- Eichhoff; Tnjpdnophellofi Bright, 1 982, is a jiinior generic synomvm of Lipdiilirnin Wollaston. New .specific .sviionymv in Scolvtidae includes: BrdcJiyspaiius moiitzi Ferrari (=C()i-tlii/liis ohtnsiis Schedl), Cdrpliolionis iniiiiiims (Fabricius) (=Cai'i>lwhonis hdlj^ciisis .Mnrayama), Cocc()tn/))('s dddiilipcrdd (Fabricius) (=Cocc(>fn/])cs tnipiciis Eichhoff), Cn/pludits sctdiricollis Eichhoff (=Cn/plidlus hrevicollis Schedl), Ficicis dcspccts (Walker) (-Hi/lr\iiiii.s stiinodiuis Schedl), Hijld.stcs pluinhciis Blantltord [=Hijlun^ops fusliiincnsis Muravama), Hi/liir^op.s intcrsfititdis ((^hapuis) (=Hyliirgi)p.s nipoiiiciis Muravama), Hi/litri^ops spcssivtscvi Eggers (=Hi/liii'li/<^rdphus qtierci Wood), Poly- •n'dplius pnixiinus iilandford {=P(ih/^rdjilius iiu/i^iius Mura\ama), Sei>Ii/t(>^enes orientdlis Scliedl), Seoli/tiipldli/pus pdniis Sampson (=Sa>li/topldti/pus rnfifiiudd Eggers), Sphdciolnipes ipierci Stebbing { = Chr\'er named Diapus alhipennis. cited ahoxc. When the Motschulslcv' hpe was r(nlisco\(M-ed (Wood 1969:118), it was recognized that two distinct hut congeneric species were representetl. Because the Strohme\er name is the juuioi- homouNin in this case, the new name stroli- nict/cri is [proposed as a replacement name lor (ilhipctDiis Strohme\er as indicated ai)o\e. Pl(iti/})iis applanatulus, n. n. rliiti/pns tijiplintdtiis ScIr-iH, 197(i, .\l)liaiKlluiilliciicimis (itcrriniitlus. n. n. lA})kcr()khs (ilcrhiims Schetil. 1957, .\miales du .Miisee H()\aK(lu ( 'oiiiro Ik'Ige, ser 8. Zoologie 56:59 (HoloUpe; i-iuaiida: lliruil)e: Belgian Congo Museum. Ter\iiren), preocciijiicd In Schedl. 1951 The generic name LrpUrwUk's ScIuhII was placed in synon\ui\ under Hijj)(>theiu'miis (Wood 1986:92). This act transferred its t\j)e- species, atcrrhnns Schedl, 1957, cited abo\e. to HypotJieuciiuis where it became a junior hom- omm of//, (itcrhmus (Schedl, 1951). The new- name <7f<;'rn//(/////.s' is here proposed as a rej^lace- ment name for (ilcniiinis ScIumII, 1957. as indi- cated aboxe. Hijpothcncinns krii oliitskai/ac. n. n. Ui/j)()tliciuiiiu\ iiiMilanini Krixolutskava, 1968. ;/( Kureu/.cn & Konoralova, The insect iannaof the So\iet Ear East ami its ecologv', p. 56 (Ilolorspi-; Kiiriie Islands; presumahK at \1adi\()st()ki. pre()ccuj)ied l)\ Perkins. 1900 Hijpotheneitiu.s iiisulanim Kri\()lutska\a. cited above, was gi\en a neuter specific name in a masculine genus. When the gender is cor- rected, as re(|uire(l under tlu^ C^ode, this name becomes a junior honioii\m ol Hi/pothcucmus insuloris Perkins, 1900, and must be replaced. The new name khrolutskat/dc is proposed as a replacement name, as indicated al)o\e. Fiti/oplilltiinis (ilricdiiiihis. n. n. Meocln/ococtis iifiicdiiii.s Schedl. 1962. Re\ista de Entomologia de Mocamhique 5(2);1079 (Holot\pe; ("ongo; Ma\uml)e; Belgian ('ongo Museum. Tennren), preoccupied l)\ Eggers, 1927 Schedl naiiK'd Xcodn/ococtcs (ifricaiuis. cited aboxe, from fi\e specimens that did not e\hii)it sexual (hflerences. Because the neotropical genus. A/Y//;/f/.v ( -Xcodn/ococtcs) does not occur in .Africa and tiiese specimens belong to the related gcMius Piti/ophfJionis. Schedls name, afriatnus. iinist l)c transh'iicd to that genus where it becomes a junior homonxin and must be replaced. The new wMwe ofriconuUis is pro- posed as a replacement for the 1962 Schedl name as indicated aboxc. Scoh/fD^cncs papucnsis, n. n. Xijlcciifptiis p/ipitiniiis Schedl, 1975, Naturhistorisches Museum W ieu. .Annales 79:352 (Holotxpe; Upper Manki 80 (;i{KAT Basin Natuhaijst [N'olunie 52 logging area, Biilolo, MoioIh^ District. New Ciiiiu-a: jt must he replaced. The new name, formosae, Naturl,i.st()risd.e.s Mu.seuin Wicni. pre.Kcnpu.l Ia ■ p,-„po.secl a.s a reiilacement as indicated ahoxe. Schedl. 1974 ^ ^ ^ The genus Xijl<)cn/j)tiis Schedl, 1975, was estahhshed with X. papuduns Schedl as the tyj)e- species. When Xi/l<)cn/})fus became a junior s\ii- omm of Sc()lylc)lij((>h/f()h/t()<^('ncs (Wood 1986:90) and the conse- quent transfer of C. pnpuanns Schedl, 1974, to Scolijto<^enes caused the name S. papuanus Schedl, 1979, to becouie a junior homouN in. For this reason, the new name paradoxus is pro- po.sed as a replacement for papuatnis Schedl, 1979, as iudicated above. Xiflchoriiuis spi)iip()sticus, n. n. EidophcUis .spinipcnnis Schedl, 1979, New Zealand Ento- mologist 7:106 (Holotxpe, leniale?; Fiji: Schedl C^ollee- tion ill Natiirhistorisches MuseuiiiW'ieii), preoccupied In loggers, 19:30 Bea\-er (1990:94) transferred Eklophflus spU\ip(')u\is Schedl, 1979, to Xi/lchoriiuis where it is preoccupied hy sj)inij)cii)iis (Eggers, 1930). Inordertorenunetheduplicatiouofnames, the new name spiniposticus is heie proposed as a replacement kn spiniju-iniis (Schedl, 1979) as indicatcnl abo\e. Xijlehonis jonnosac, n. n. Xijichonis foniio.sanits Browne, 19S1, koiitsu 49(1):1:)1 (llolot\pe. female: Ilualien (Formosa) tf) Yat.su.shiro (Japan), imported: British Mu.seuin [Natural IlistotA]), preoccupied In Fggers. 19.30 When Browne named Xijlehonis forniosauus. cited aboxe, he (nerlooked pre\ious usage oi" this species-group name in the combination Xi/le- bonis nuniciis foniwsanus Eggers, 1930:186. Because the Browne name is a junior homonxm, Generic Ti^ANSFERS of Fossil SC;OLYTIDAE Drijococtcs (liluvialis (Wickham) l'lli/(iplillii>ri(lc(i (liluiidlis \\ ickliam, 1916, State Unixersity of Iowa. Eahoraton- of Natural IIistor\; Bulletin 7: IS (IIolot\pe: fossil in Miocene, Florissant, Colorado: not located) The photograph of the holot)pe that w-as pub- lished with the original description of Piti/oph- thoridca diluvialis Wickham ( 1916:18) suggests that tins species is a member of the genus Dn/ococtcs. Because there appears to be no justification whate\er for recognizing a separate genus, the name Pitijoplifhoroidcs is placed in synonymy under the senior name Dnjocoefcs, and diluvialis is transferred to that genus, as indicated aboxe. Hi/lcsiiuis hijdntpicus (Wickham) Apidoccpliiihis }u/(lri)})inis Wickham, 1916, State Universitv III lo\\:i. Laboraton of Natural Iliston; Bulletin 7:18 (Holotspe: fossil in Miocene, Florissant. Colorado: not located) The photograph of tlie holotxpe that was pub- lished with the original description of Apido- ccphahis lu/dropicus Wickham indicates that this species is a member of the genus Hi/lesinus. The generic name Apidoccphahis is here placed in .synonymy imder Hijlcsiuus and the fossil spe- cies hijdropicus is transferred to that genus, as indicated above. Plilocotrihus ziiunicniumiii Wickham, to C>urculionidae Pliliicdlrihu.s ziiiiincniianiii Wickham, 1916. State Uni\er- sil\ ()l low:i. Lalioratonof Natural Histon-, Bulletin 7:19 ( I lolohpe: fossil in .Miocene. Florissant, ('oloratlo: not located) The photograph of the holotxpe o\ Phhwofri- hus zinintcrnunnii Wickham (1916:19) that was [)ublishedwith the original description indicates that this species is not a member of this family and nmst Ix^ transfernxl from ScoKtidae to the famil\- (Jurculiouidae. New Synonymy in Scolytidae (Uisiuodcrcs Eichhoff CoMnodcrcs Eicliln)!!, 1S7S. Societe Entoniolo^iijiR' de Liege, Memoires (2)C()siiu>elcrcs Nobuchi. 1981. Kont\ii 49(1 ):16 (T\pc- sprcii's: I'sciKlocosiiuHlcrcs atictiiiatiis Nohuchi =CV).s- I node res inoiiilhcllis I'iclilioll, original (Icsii^natioii). ,\V(c siiiiiinijxui TIk' ^('iius FscikIocosiikxIci'cs Xohuflii. citctl al)<)\'(\ was named lor Pscu(l(>c()s))U)(lcrcs atlciiuatus Nobuchi, 19S1. The photojiiiaph ol iho hpe material that accompanied the oriij;inal description is an ilhistration of ('.osnuxicrcs iiK'nilicollis Eichhofi, 1878. The Nobuclii genus is an ohxions .sviionvui of Cosinodcrcs. The sj)ecilic s\ iionymy requires confirmation, l)nt is almost certainlx' correct. Dnjocoetcs Eichlioff l)n/()cc)iii:s Kic-liliotf, 1S64, in Sthiciik, Hii'st-ii unci Forsclmngeii in .\niur-Landf 2:155 (T\pf-,specirs: Biisfnchiis tiut()lius Ratzel)uit^, snlisequent designa- tion InWood 1974) I'id/oplithoridca W'ickliaiii, 191fS. .State Uni\ei".sit\' ot Iowa, Lalioraton' of Natural Histon. Bulletin 7:18. figs. 27-28 (T\pe-speeies: Piti/oplithoruica dilurialis Wickliani. orig- inal designation). Xcic si/ndinfiuii Tile figtu-es of the liolotxpe of Pifijopli- tlioridcd that were publislied with the original d(\scri[)tion indicate that the tspe-species, P. (liliiiialis, is a meml)er of the genus Dn/ococtcs. (,'()nse(|uentl\, Wickhanis name Pifi/oplifhor- ulcii is [ilaced in s\iion\ni\ under the senior name, as indicated aboxe. Hijpothenemus Westwood lUijH'ihdicuins W'esbivood. 1836. Entoniologieal Soeiet\ ol London, Transactions 1:34 (Tvpe-species: Htjpotliciicnius cniditus Westwood. monobasic) Macrornjphaht.s Nobuchi, 19S1. Kontvu 49(1 ):14 (Tvpe- speeies: Mdcrocnjpludns ohlougna Nobuchi, original des- ignation). Frohaljje s\non\in\' The g(^nus Macrocn/plialiis Nobuchi, cited abo\e, was named InrMacrocn/phalus olAoii'^us Nobuchi. .'\ close examination of the photo- gra])hs of t\pe material pul)lislied with the orig- inal descriptions clearK indicates that the species ohlonous is composite. Tlie "male" illustrated is a female of Ht/potlwncnnis Jiiscicollis Eichhoff a sj^ecies ra])idl\ b(^c-oming [)antropical in distribution through commerc(\ rlie ■female' is a female of another //7/)e//H'(/r///?/\ speci(^s that cannot be identified with certaint\ from the illustrations. It repre- sents an ob\ious introduction from another area. The name Macrocn/pluilus is lu^-e placc^d in sNuonxniN until tlie name ()l)l(»i<^iis can be clarified. Lipai-tltnim Wbllaston Lipaiiltnnii Wbllaston. 1854. In.secta Maderensia. p. 294 (T\pe-s|X'cies: Lipaiihniiii hUiihcrnilatuiii Wbllaston. original designation) 'I'njpuiioplicUos Bright. 1982. Studies on Neotropical Fauna and Kn\ironnient 17:166 (T\pe-species: TnipauophcUos iicc(>])iitus Bright). Newstpioinpni/ Tii/paiioplK'Hos iiccopimis j-iright was based on a unicjue female collected bv Schwarz at Cayamas, (^uba. I examined this specimen in 1976 at the U.S. National Museum and recog- nized it as a (listincti\e, undescribed species of Lipaii]iruiii.T\\(.' holot\pe was recentk' reexam- ined and compared to otluM- Lipartlii-uni spe- cies. Because I am unable to see an\ generic characters that might possil)l\ distinguish Tnjpan()j)licll()s front Liparfhnou, Bright's generic nanu^ is placed in s\ iionxinx- under the senior name as indicated abox e. The species, L. necopinus, is uni(jue among .\merican Lipar- thniin species in liaxing a double row of scales on the decli\ ital interstriae. P()li/li/t()gc)ics l'',ichhoff". 1878, preprint of.StKiete Roxaledes Sciences de Liege, Memoires (2)8:475. 479 (T\pe-spe- cies: S(()h/I()l)(>nis /w/g('»i.v/.s .Muravama, 1943, .Annotationes Zoologicae Japonenses 22:99 {Lect()t\pe, male: District of Halga, Manclioukuo, China; U.S. National Museum. present designation). Xcic sipiniupin/ Caqyhohonis IxiU^cnsis Muravama was named from one male and one female syntvpes mounted on separate microcards on one pin. The male is in recognizable condition and is here designated as the lectot>pe for this Mura- vama name. The "female" has been damaged and only the head remains; its face is entirc>l\ iuunersed in glue. This lectotype was compared to males of my .series of C. Diininiiis (Fabricius) from Europe and northern Asia. While no two males of this species are ever exactly the same, tlie halgen.sis lectotvpe is of the same size and proportions as C niininiiis and falls well within the limits of variabilit)- and geographical range for this species. Because only one species is represented by this material, the name balgcnsis is placed in .synonymy as indicated above. Coccotnjpcs dacttjlipcrdd (Fabricius) Bnstrichus dactijlipenla Fabricius, 1801, Systema Ele- utheratoruni 2:387 (S\ait\pes, female; date pits inter- cepted in Europe; Copenhagen Museum) Coccotnjpes tropicus Eichhoff, 1878, preprint of Societe Royale des Sciences de Liege, Memoires (2)8:312 (Holo- tvpe, female; .America Meridionalis (Peru); Hamburg Museum, lost). New .siptoiii/iiii/ Eichhoff states in the original description, cited above, that his Coccotnjpcs tropicus is near C. dactijlipcrda. Because the description fits the pantropical dactijlipcrda. because there are no knowii endemic Coccotnjpcs in South America, and because the unicjue holotvpe and only known specimen of tropicus was lost in the destniction of the Hamburg Museum, C. tropi- cus is here placed in synonymy under the senioi name, as indicated abov^e, as a means of dealing with this unidentifiable species. Cnjphalus scabricollis Eichhoff Cnjphalus scaljiicollis Eichhoff, 1878, preprint of Societe Rovale des Sciences de Liege, Memoires (2)8:36 (Holo- tvpe; Hindustan Asiae; Hamburg Museum, lost) Cnjphalus hreiicolli.s Schedl, 1943, Entomologische Blatter 39(l-2):36 (Leetotvpe, female; Bagnio, Luzon, Philippineu; Naturhistorisclies Museum Wien, desig- nated b\ Schedl 1979:47). \'cw sipidiiiinu/ The holotvpe of CrijphaJiis scabricollis Eichhoff was lost in the 1944 destiiiction of the Hamburg Museum. My concept of this species is based on a series of specimens in the Forest Research Institute, I>=>hra Dim, that was com- pared 1)\- Beeson and Eggers to the hoK^tvpe before it was lost. Mv series was compared directly by me to this series; then these speci- mens w t're later compared to the holot)pe of C. brcvisctosus Scliedl. All represent the same coimnon, widely distributed species that infe.sts various species oi Ficus from bidia to the Phil- ippine Islands. For this reason, Schedls name C. brcvisctosus is here placed in svnionvmy unck'r the senior name, as indicated above. Ficicis dcspcctus (\\'alker) llylcsiiius cicspcdus Walker. 1859. Annals and Magazine of Natural lliston (3)3:261 i llolotNpt'; Cevlon: British Mu.seum [Natural Histon]) Hylcsiiius siniiiKniiis Schedl, 1951, Bishoji .Museum Occa- sional Papers 20(10): 142 (Sviitvpes, male; Upolu, 1992] NOMENCL.\TUHAl. Cll A\(;KS IN PLATYI'ODH) \i; AND S( iOLVniMK 83 Tapatapao; British Miisriiiii | Natural llistorvj and .NaturliistorisflK's Muscuiii Wiciii. Wu \i/iu>iiijiiii/ Tli(^ Schc'dl sMihpes of Hylesiinis saDioanus Scliedl in the W'ien Museum were examined 1)\ me and were c()m[)ared dii'eetK to m\ liomo- t\pes ol H. (Icspcciits Walker. C)nl\ one speeies was reeoifnized. On {\\v hasisof tliis c'<)ni[)ai"i,s()n. Scliedls name is plaeed in s\non\in\. as indi- cated abo\e. Hi/lasics pliiiiihciis Hlandloixl Ih/liislcs j)liiiiiliiii\ 15landford, 1894, Entomological Socich oi London, Transactions 1894:57 (S\'nhpcs; Nagasaki ct a Ilioga, Japan: Brnssels Museum) //(//» /"ijo/n fttslimiciisis MuraNama, 1940, Annotationcs Zoologicac japoncnsis 19:235 (Lectohpe, feniide: Fuslicn. .Mancinuna: U.S. National Museum, present des- ignation). Scic si/noin/ini/ Hijliir^Dps fiisliiiitoisis Mnraxama was hased on one male and one iemale s\iit\pes that are mounted on one pin. The callow female is mounted upright; the callow male is moimted upsitlc> down with the dorsal surface imbedded ill glue. The female is here designated as the lectot\"pe for //. ftishiniciisis Mura\ama. This lectot\pe was compared directK t(i ni)' Ussuri specimens of Hylastes pbimhens Blandford that were identified b\" Kurenzow These specimens clearlv represent one species. For this reason, fuslunwnsis is transferred to Hi/lastes and is placed in s\non\-my under the senior name, as indicated aboxe. I li/liirps niponiais Muraxama was examined and com- pared directK to m\ long series ol //. ntlcr- stifiali.s (C^hapnis) from |apan (detcMiiiiiicd 1)\ Nobuchi) and Siberia ({l(4(M-iiiiii('d b\ Kiiicii- y.ov). The Miiraxaiiia holotxpe is an axciage Japanese specimen ot this species. The name nipoiiicus is here placed in sxtioumux under the senior name as indicated aboxe. Hifltir^ops spcssivtsevi Eggers Htjlnrgops spessivtsevi Eggers, 1914, Entomologisclie Blatter 10:187 (Lectot\pe, male; Ostsiberien, USSR; U.S. National .Museum, designated bv Anderson & Ander.son 1971:;30) Htjlur'^ops niodcstus .Muraxama, 19.37. Tentbredo l:.3fi7 (Syutxpes; Pic Biro du Kongosan. Korea; .\Iura\ama C^ol- lectiou in U.S. N;ition;il .Museum). Ncic sijnont/nit/ Txxo Iemale six'cimens in the .\hnaxama (Col- lection are labeled as "paratxpes" (.){ Hijlur'^ops ni()(l('siiis .Muraxama. Their label indicates that thex xxere taken at "Yalelomia. Mancliiiria, 25- MII-f94() bx \. Takagi"; a second label gixes "Manchoukuo, (,'ollected 1940, J. Miuaxama, Hylurgops nuxlcstus Muraxama, parat)pe." Because this Muraxama species xx'as named in 1937, it is presumed that these "paratxpes" are actuallx metatxpes that xxere compared bx- Mtnaxama to his t\pe series. Murax ama told me in 1955 that xirtuallx' all of his Manchurian col- lections had been destroxed during World War II. Con.seqnentlx, the aboxe "paratxpes" are probablx the onlx knoxxii existing .specimens of nuxlcstus that are reasonablx autlientic. These "paratxpes" xx'ere compared directlx to m\' homotxpes of H. spessivtsevi Eggers and xxere found to be normal, axerage specimens ol this Eggers species. For this rea.son, the name iiuxl- estiis is placed in .sxnonxinx under the scMiior name, as indicated aboxe. Ips stchhiiigi Strohmexer lp\\trhhiii<^i StroinncNcr, 1908, Entomologi.scben Wbclien- hlatt 25:69 (Sxnhpes. male. lemiJe: Kula. Himalava occidentalis: Strolunevi'r (Collection. Eberswald. Forest Research Institute. Dehra Dun, etc.) Ijis sclmiutzeiiliofcn llolzschuh, 1988, Entomol()gic;i Basilieusia 12:481-485 (Ilolotxpe, male; W'e.st-Bluitan, Cham^ang, 3000 m: Naturhistoriscbes Museum Wien). .V(7r siiii(})iijiiit/ 1 examined txxo sxiitxp(\s ol Ips stehhin^i .Strohmexer in the Forest Research institute (.'ollection, Dehra Dun, as xxell as approxi- matelx 2. ()()() other specimens of this species from l^ikistan, Nepal, Bhutan, and India (Kashmir, Punjab, Uttar Pradesh) from species of.\/>/'r.s. C.idnis. Picra. and riniis p(>h/^raj)hiis kaiiuo<-lii Nohuelii, 1981, KontMi 49:1.3 (Il()lot\pe, female; Sliionomisaaka, \\'aka\ama: Nobnchi Collection, Ibaraki) Pohj. female: Melialkhali [Bnrma?]: Forest Research Institute, Dehra Dun). Xcu: si/noiiiiiuij The female holotspe and two parat)pes of Ki])])onopohj<^ropluis kaiinorhi Nobuchi were compared directly to one another and to the t\pe series of Poli/<^rapliiis cfncrci Wood bv me and were foimd to represent onK' one species. The junior name, qiicrci, is placed in s\iionvm\' as indicated above. Pohj<^raj)liiis f)ro.\ii)iii.s l^landford Pohj^raphus proxiinus Blantllord, 1894, Entomological Society of l^)nd()n. Transactions 1894:75 (Sviit\pes, 2; Sapporo, Japan; British Museum [Natural Ilistonj^ P<>ltltin 7:279. 282 (IlolotApe. Icniale: Nishiniata, Aki C^onntA, Kochi pref., Japan; U.S. National Museum). Sen: si/uoiti/iiii/ The unique female holotApe oi' Poh/uu>rphns oriciifalis Sclietll, 1971. Opu.scula Entomologica 119:11 (Holot\pe; Clliana, BekAvai; Naturliistorisches Museum W'ieni. \civ si/ni>iu/uu/ The holotvpe of Crijplialoinoiylius orientalis Schedl, cited above, was compared directly bv Schedl to the holotvpe of C n/phaloinorphus bracleri Bro\\aie, cited abo\e, and (as indicated in a note in his collection) he concluded that only one species was represented. I examined the Schedl holotvpe and compared it to speci- mens identified b\' Schedl as hradch Brcmaie and reached the same conclusion. In view of this, the name orientalis is here placed in svii- on\in\' as indicated aboxe. Scoh/toplati/pns pairus Sampson Snihjtopldti/jni.s parvus Sampson, 1921, .Annals and Maga- zine of Natural I Ii,stoi-v (9)7:36 (Ilolotspe, male; Sarawak, Mt. .Matang; British .Mu.semn [Natural Histon]) Scolt/foj)l(ifi/})us nifianula Eggers. 1939, .\yV\\ for Zoologi 31.'\(4):.36 (llolot\pe, female; Kamhaiti, .Nordost-Birma, 7()()() ft.; Stockholm Museum). Nnr sipioiu/Dii/ Four specimens of Scolt/toplati/piis parvus Sampson that were compared to the holotvpe by Brownie were compared directh" b\' me to nine specimens in the Forest Research Institute, Df^hra Dun, that had been identified bv Eggers as his S. nificaiida. The\- all represent the same species. Assuming that Eggers correctlv identi- fied his species, tlu^ name s. nificaiida nnust be placed in sviionx ni\ under the senior name S. pan lis. as indicated abo\ e. Spltacrotri/pcs cjiicrci Stebbing Sphiicrotn/pv.s (jurivi Stehhing. 1908. hulian Forest Mem- oirs, .series 5, 1(1):5 (Sviitvpes, sex?; India. N-\V Hima- la\;i, Kunuimi: Forest Research Institute, Dehni Dun, lost) ('ludincsiis 0(>hiiUis Stehhing. 1909, Indiiui Forest Mem- oirs, Forest ZoologN- .series 1(2):21 {Hok)t\pe. Kathian. (Ihakrata. U.I'., India; Forest Research Institute, Dehra Dun). Preoccupied 19921 NOMKXCLATUHAI, CMl WCI'.S IN Pi, ATYl^ODIl) AI! WD SCOI.^TIDAP: 85 SjihdcwtnijH'S tectus Beesoii. 1921. Intliaii P'orestiT 47:514 I ll()I()t^pc^ sex?; Katliiaii, ('Iiakrata, V.\\. India; I'orcst Hcscarcli Institute. ndiiM \1\\\\. ant i\lk-^.\cif'siiii(nii/iiii/ The .series of SpJiaerotn/pes cfucrci Stehhintj; in llie Forest Research Institute, D(^lira Diui, collected h\ Stebbing and otht^^s, does not include oripnal specimens. H()we\(>r. Steh- !)inii;'s identification, description, and notes cleaiK indicate that this name was correctlx applied to his .series. This material was examined and compared directK to the holotxpe of C'lti7inicsiis globulus Stebliing In' me. Both sets olspeci uKMis clearK represent tfie same species. Beeson recognized that the name S. g^lobosiis was preoccupied hv Blandford and proposed the re{)Iacement name S. tectus for St(^b!)ing's species. The senior svnon\ni, .S. (jucrci Steb- bing, lias priority" and is used to designate tliis species, as indicated aboxe. Sui'iis niisiituii (Eggers) Ihliirrlii/iiclius iiiisiiiuii Eij;ijers, 1926, Kiit()in()l()u;i.sclu' Blattrr22:133 lHolot:\pe. temair: |apan: Urakawa 1 1 loko- ilate]: U..S. National Museum) SjiliacrDtnjpcs rinitroveisae Mura\aiiia. ]95(), Iiisrcta .Matsuiniiraiia 17:fi2 ( Lectotxpt'. tenialc; Daidoniinaini- \aina. Kotlii pref.. Sliikokiii. |apan; l^S. National Mnsciini. present designation). Xcw .\iiiu>iii/mii xMura\ama named Sphacrotnjpcs con- frovci'sae from six female .specimens mounted on two pins. Although he refers to a t\pe, a holotxpe was not marked or labeled In Mura- \ ama. The^ two specimens mounted on separate points on one pin are coxered by glue and are recogni/ed with difficult\. On the other pin, the third specimen from the top (or the second one up Irom the bottom) is in the best condition and is here designated as the lectot)pe of coii- troiersdc. These specimens were compared directK to m\ homotApes and other .series of Siiciis niisi))t(ii in m\ collection and are identical in all respects. Because oiiK one species is rep- resented, the name coiitrover.me is placed in .s\iionym\ under the senior name as indicated .il)()\'e. Toitiiciis i)rci i})il()siis (Eggers) Blnslopliapis hrciipilosiis Eggers, 1929, Entoniologisclii' Hlatter25:103 (Svnhpcs, 2; [Fnkien] China: Kggers (Col- lection) Bl(isiopli(i'j^\i\ khds'uiHHs .\Inra\ania 1959. HrookKn taito- niologieal Societs. Bulletin 54:75 illolotxpe: .Shillonpic homotvpes of B. klidsiainis Muraxama. and mv homotxpes of B. l)rcvipil()sus Eggers were all compared directly to one another. Althougli the As.sam specimens are st)me\vhat larger, all share the \en short interstrial setae and are here placed in the same species. This .species is ver\' closel\- allied to pUiipcrda (Linnaeus) and is distin- guished with some difhcnlt\' from that species b)- the .setal characters. It is cmrentK' placed in the genus Tomicits imd(M- the senior name hrciipiliisiis as indicated abo\e. New iN'i'KoDi ctions Hijhistcs opacus Erichson Hijlastcs oparua Erich.son. 1S36, .Arehix fiir Natnrgcschichte 2(1):51 (Syntxpes; presumabK' Germaiiv; Berlin .Museum) A series of Hi/lasfcs opaciis Erichson was col- lected near tlie eastern tip of Long Island on Fishers Island, Suffolk Co., New York, USA, 23 Ma\' 19S9, from an Ips plieromone trap, b\' T W. Phillips, (circumstances of the collection sug- gest that this species has established a breeding population at that site. This species is conunon throughout the pine belts of Europe and north- ern Asia and it has become established in pine plantations in Soutli Africa. While it breeds pri- mariK in the roots and stumps of pin(^ (Piitiis spp.) and spruce {Ficcd .spp.), it is known as an economic p(\st of small .seedlings of these trees. Plilocosiiiiis (initaliis Heitter I'hlncDshiiis (innatu.s Heitter, i8S7, Wiener Entomologisehe Zeitung 6: 1 92 ( I lolotxpe, male; Syrien; Naturhistori.sches .\Inseinn \\ ien) Tliis species was recentK foimd to be estab- lished in Los .Angek's Co.. Califoniia, USA, in a broad area in sufficient numbers to cause eco- nomic losses in Cn})ri'ssus spp. It was prexiously kucmn from (nprus, S\ria, and Israel, where it is an impoilant pest of (jiprcssiis spp. New Species C'l/cloiiiipidioii siiha; a finc^ median carina from center ol conca\it\ to (>pistonial margin, usually higher on lower third, without a denticle near epistoma (as seen in co.sticcps). Xestitiu-e hairlike, ratlier sparse and inconspicuous; not conspicuousl) longer and more alnmdaut on margins as in costiceps. Pronotum 0.9 times as long as wide; similar to co.sticcps except punctures more shaiply, more stronglv impres.sed, hairlike setae shorter, less con.spicuous. EKtra 1.7 times as long as wide, outline similar to costiccps: striae 1 slightl), others not impressed, punctures rather small, round, deep; interstriae as wide as striae, smooth, shining, punctures minute, confused, moderately abun- dant. Declivdt)' gradual, not steep, evenly, rather narrowlv convex; sculpture as on disc except interstriae 1-3 each with a row of about six minute granules; \estiture much less abundant than in cosficeps . interstrial rows of erect setae rather slender, each about as long as distance between rows, groimd cover recumbent, each seta about half as long as erect setae. Fe.MALE. — Similar to male except frons convex, carina less conspicuous. T^TE MATERIAL. — The male holot)pe, female allotxpe, and two male paratxpes are from Rot()nia, New Zealand, Hopk. US 3726-U, C. L. Masse\. The holotxpe, allot\pe, and parat)pes are in m\ collection. Poh/j^raphus fliifsi. n. sp. The name Spoiif^occnis tliitsi Beeson ( 1941 :387), nomen nudimi, was used b\' Beeson without a description or designation of t\pe material, either in the original publication or on specimens in his collection. Browne (1970:550) recognized this deficienc\' and attempted to correct the problem b\- designating a Beeson specimen as "lectot)pe" and presenting a description of it. Howe\'er, in order for a lecto- t\pe to become a primaiy t\pe it must be validly designated (Code of Nomenclature, 1985, Arti- cle 74a). In the present case, because Spo)i<^occrus fliitsi Beeson was a nomen nudum, a t)pe series did not exist; and because there were no sviitxpes, a lectotvpe could be not be \alidl\- designated. Therefore, regardless of the action h\ Browne (1970:550), Beesons nomen nudum remained inxalid. The name S})on<^otarsus is currentK" a s\nomni of Poh/- ^r(ij)lnis\ consequentK; the .species cited as ihilsi is here transferred to tliat genus (^^bod 19Sfi:56). I'^or the [)uipose of \alidating this name, Poh/- oraphus tliitsi is presentetl here as new to sci- ence. It is allied to P. kainiocliii Nobuchi, from Bunii'i, but it is distinguished In the much larger size (4.7-5.S iinn). In the completely dixided e\e, bv the laigcr pronotal punctures, b\ the more slcMider eKtral scales, and In the host. 19921 NOMEXCLATUIiM, CllWClvS l\ Pl.ATVI'ODIl ) M', AND SCOLVPIDAE 87 Browne (1970:550) presents a lull (Icscriptioii oi P. fJiifsi. Browne's inxalid '"l('et()t\]H'" is lierc (k'si^natccl as the female liolotxpc ol /' lliitsi. Except that the tApe loealitN. Xamina Kesene (Burma) is IneorrectK spelled. Browne's data are correct; it is in the British Museum (Natural Histon K The male allotvpe has the lower hall of the Irons shallowK. almost concaxt'K impressed on the median third; it hears data identical to the holotvpe and is in m\ colK^ction. One female paratspe in m\ collection and 47 parat\pes of both sexes in the Forest Research Institute bear data identical with that of the holot\]')e. TriotcDiiuis pilicon}is. n. sp. This species is distinguished from zei/ldniciis Wood, below, h\ the slightK larger size, b\ the lighter color, bv the coarser pronotal punctures, l)\ the \er\' large, median horn on the male \ertex, and bv tlie \en' small mandibular spines in the male. Male. — Length 1.5-2.2 nun (female slightK smaller); 2.5 times as long as wide; color brown. Frons strongk; trans\'erselv excaxated, feebh' if at all concaxe between eyes; a veiy large, dorsoxentralK flattened, median spine on xertex (this spine often more than twice as long as scape); surface smooth, shining, glabrous, dorsal surface of spine strongK' pubescent, the.se setae ver\' long. Pronotum ver\' slightly longer than wide, snb- (|nadrate; surface smooth, shining, punctures coanse, deep. Vestiture sparse, rather short, \en long and conspicuous on lateral and antcMior iiiargins. Ektra similar to zci/laiiicus exce[)t punctures slightK' smaller; setae more slender, decli\it\' more broadlv com ex. Fe.MALE. — Similar to male except: Irons weakK-, transversely impressed (stronge-r than f(Mnale zei/lanicus), moderateK punctuicd: w ithout spines on vertex or mandibles. Type M vrEHIAE. — The male holotxpe, female all()t\]H'. and six jiaratxpes were taken at Chikalda, Malgahat, C.P.. India, 16-X-193fi R.R.D. 106, R.C.R. 181, Cage 660. Iroui EiipJiorhid sp. b\- N. C. Chatterjee; all are mounted on hvo pins. The holotxpe is the n[)permost specimen and the allot\pe is the third specimen downi on the same pin. The holot\pe, allotxpe, and parat\pes are in ni\ col- lection. More than 480 non-t\pe specimens were examined at the Forest Research Institute, Dehra Dim. Ironi th(^ states of Karnataka, Madliya Pradesh, and Maliarashtra from Eiiphorhid spp. Xi/I chorus iiia^nificiis. n. sp. This species is distinguished from X spdthi- peiinis Eichhoff b\ its larger bod\' si/e. In the much mon^ broadK, less steepiv comex elxtral declivit); In the nmch less strongK' impressed eKtral striae, and In other details described below. It is a unich stouter species than X. princcp.s Blandlord. In a series of spatliipciinis from the same localit\ and date, the strial punc- tures on the disc are mostlv confluent; in iiui'^- nificiis the\' are mostlv separate. Female. — Length 5.6 nun (paratspes 5..5- 5.7 nun). 2.3 times as long as wide; color xeiA' dark browni. Frons about as in spafliifx-nnis. Pronotum similar to spathipennis except: anterior margin less stronglv produced (.straighter), serrations less well dex'cloped: discal area smoother, punctures smaller. Elvtra similar to spathipennis except: form slightlv stouter, posterior margin more broadK" rounded; profile ol upper decli\it\' more strongK', less exeuK' arched; striae nnich less strongK impres.sed on di.sc, not at all impn^ssc^d on declixitx ; interstria(^ much more broadK con- \ex on disc, flat on declix i(\. punctures smaller, more numerous, more ob.scure and almost ne\er replaced In* minute granules on declix itv; declivital interstriae 2 and 4 ne\er with setae (a few short .setae present in spatJiipennis). T^TE MATERIAL. — The female holot\pe and five female paratopes are labeled: lunin [pre- .sumabK Peru], ()'l-IX-79, S. Poncor, EESC. 5- 80. The holot)pe and paratypes are in m\ collection. Lite HATE RE Cited I5l \\ i:n. R. A. U)91. \r\\ s\-nonvmv and taNoiinmic ciiangc-s in Pacific .ScoKtidac (Coleoptera). Natnrlii.s- torisclie.s Mn.scnni W'ien, .Annalcs, serie B, 92:87-97. Bkkson (". E. C. 194L Tlie ecologx' and control of the forc.st in.sect.s of India and the neigliborino; coniitries. Pnhlislied 1)\- the anthor, L>ina Dim. 5 + ii + 1007 pp.. 20;3fig.s. 36pis. BuowNK. F. C. 1970. .Some .Scolvtidae and Platvpochcke (C'oleoptera) in the collection of the British Museum. journal of Natmal I liston 4:539-583. SciiKi)!.. K. E. 1957. ScoKtoidea nouveaiix du Congo Beige. II: Mi.ssion R. 'Ma\iie-K. E. Schedl 1952. .Annales du .VI usee Royale dn Congo Beige. TerMuen, serie 8, Sciences Z(X)logiques 56:1-162. Great Basin Naturalist [Volume 52 . 196]. Fauna of the Fliilippiius, IX. I'liilippiiu- . 1972. New records and species of American Journal of" Science 9()(l):87-96. Plat\poclidae (Coleoptera). (ireat Ba.sin Natur;ilist 1964. Zur Sviionvniie der Borkeiikaler, W. 31:243-253. Reichen!)acliia 3(29):30.3^3I 7. . 1984. New generic .sMionvmv and new genera of . 1979. Die Tvpen der Saninilung Schedl, Faiiiilic Scolytidae (Coleoptera). Great Basin NaturiJist Scolvtidae (Coleoptera). Kataloge der wissenschait- 44:223-230. lichen Sannnlungen des Natin-historischen Museums . 1986. A reclassification of tlie genera of in Wien, Entomologie 3(2). 286 p. Scolvtidae (Coleoptera). Cweat Basin Naturalist Mem- WOOD. S. L. 1969. New .svnonvnn and records of oirs 10. 126 pp. Platspodidae and Scolytidae (Coleoptera). Great Basin Naturalist 29: 1 13-128. Received 6 januanj 1 992 Accepted 24 januanj 1 992 (ircat Basin Naturalist 52i 1 i. 1992. pp. S9-92 NOMENCLATURAL CHANGES IN SCOIATIDAE AND PLATYPODIDAE (COLEOPTEUA) StcpllCH I .. \\ 0()(1 .VliSI'KACr. — New s\ii()ii\iii\ in ScoI\ tidac includes C.ii/pluiliis picfdc i Hat/churi;, 1S37) {=Cn/pluilH.s siih(lcj)r(:ssus Kijgers, 1940), Gnathotnipes lon'^iusculus (Scliedl, 1951 ) {^C^iuilliolrupcs ciliiitus Schedl. 1975). Hiipoilwuvmus cniditus Wc'Stwood ( = Steph(inodercs coiitniiinis Schanfnss, 1891). In ^lat^p()(lidae tlic new name Plfiti/jiiis ahniptifcr i.s proposed as a replacement for the jnnior liomonNin Plati/pii.s ahntptits Browne. 1986: t\pe-species designations are proposed for tlio genns-gronp names Scittopi/'^its Nnnberg, 1966. Pi/<^(Hl(>liiis Nunherg, 1966, Mix<)})i/i)i/"liapnis, IS65 (=Crossot(ir.sus nicohariais Beeson, 1937), Phiti/pits ahditus Schetll, 1936 ( =Phiti/ptis transHus Scliedl, 1978). Phili/piis nifftsifrons ,Scliedl, 1933 ( =Pl(iti/pits pretio.sn.s .Schedl, 1961 ), Platypus tirio.seii'iis Reicliardt. 1965 i =l'l(ih/pjis silicdli Wood, 1966), Trcpti>phiti/j)us midtipoms Schedl, 1968 (=Platiipus fastiiosus Schedl, 1969). Kct/ words: Scolijliddc. I'liili/pailitliii-. ('olcoptcni. iioiiicncldtinv. The following page.s record iteni.s affecting lion ienclati.n-e in Scolvtidae and Platvpodidae tliat are pre.senttxl here in order to make tlie changes a\ iiilahle for the world catalog now in preparation for these families. Included are three ca,ses of new- specific sviionvmy in Scol\tidae. In Platypodidae are (a) one new replacement name for a junior hoinornm, (b) 10 t\pe-.species designations for genus-group names, and (c) six new ca.ses of spe- cific s\iioimn\. Nkw Synonymy in Scolytidae C.i'ijjilialtis piccdc (,Kat/el)in-g) Boslrichus piccli(>i)i/ffts Schedl, 1939, International Congress of Ento- molog); Procei'dings 7:402-403, t\pe-species: Cr<«.s- otarsus hohcinani Chapuis, designated by Schedl 1972 Scut(>i)t/ffis Nunherg, 1966, Re\iie de Zoologie et de Botaniqne Airiciiines 74:1S7-1S8, t\pe-species; C/v«.s- otarsit.s nipax Sampson, present designation. Nnvsipwiii/im/ Pijgodolim Nunberg, 1966, Revne de Zoologie et de Botanicjne Africaines 74:1S(S-189, tvpe-species: C'/o.s.s- otaisus vc. Pmceediiigs 7:401. t\pe-species: Cross- (il(irsu\ trcjxiiKiliis Chapuis, prcst^nt (k'siiiuatioii The generic name Trcptoplati/pus Schedf cited aho\e, was named witliout the designation of a t\pe-species. To renioxe this deficiency, a t\pe-species is designated al)o\ e. as indicated. New Syxoxymy in Platypoimdae Cro.ss(4(irstis cxtcnicdcutatus (Fainnaire) Pldli/jiiis cxtcnu'dnitdtiis Eairniaire, 1S49. Rexuc et .\Iag- asin de Zoologie Pure et Appli(juee, ser 2. 2:78 (Molo- tApe. male: Taiti: Mu.seiim Nationd d'Histoire Naturelle. Paris) l^iapits tdlnrac Stel)bing. 1906. Departiuental notes on insects tliat affect forestiT (Calcutta), No. 3, p. 418 (Smi- tvpes; India: Madras Presidencw N. Coimbatore Forests: Forest Hi'searcli Institute. Delira Dun. Xcic si/iioiit/ini/ The species Diopiis tahirae Stebliing, cited ah()\e, was described as occurring tliroughout India in economicafl\' significant numbers. Reports from 1906 tlirougli 1908 repeat the original report. It was last mentioned in original literature in Stebbing 1914 (Indian Forest Insects, p. 626), where it was transferred to tlie genus Platijpii.s. There are no specimens under this name or host {Shorca tdhira) in the Forest Research Institute, Dehra Dun, nor is the t\pe localits' represented on an Indian platspodid. The Stebbing 1914 illustration is of a Cross- otarsus species, probably cxfcntcdoitdfus (=saiin(lcrsi). Becau.se so main' of Stebbing's Platxpodidae in the PT-II (Collection are misiden- tifications of this species, ialunic is placed in s\non\niy under cxlcntcdoitatiis, as indicated aboye, based on the Stebbing illustration in the absence of other e\idence. The fact that it was said to be a common, economic species supports this placement. Cr()ss()t(irsu>i IcnniiKitiis (Chapuis Crossotami.s tci-miiuitiis Cliapuis, 1865, Monographie ties Plat\pides. p. S3 (Holot\pe, male; Singapour; British Museum [Natural Histor\], London I Cros.mtaisus nicoharicus Beeson, 1937, Indian Poorest Records, Entomolog\' 3:86 (S\nt\pes; Nicohars: i'.ixr Nieohar; fairest Ixestarcli Institute. Delna Dun). XiCW Sl/IIOIltlllll/ The male hol()t^pe and .se\en parat\pes of CU'ossotarstis nicoharicus Beeson. cited abo\(\ were compared In- me directly to the Beeson series of C. vciuistiis (.'hapiiis (=C. terminatiis Chapuis), cited abo\(\ and tAyo of these to m\ series of C. feniiiiiafits. In the absence ofdistin- guishing characters, all were considered to rep- resent the same species. For this reason the name )iicohariciis is placed in s)non)m); as indi- cated ab()\(". Fifiti/pus (ilxlitus Schedl rlaitjpus (ihflilii.s Scliedl. 1936, Hexiie Fran^iiise trEutoinologie 2:246 (Holot\pe. male: Naturliistorisches .Museum W'ien) Pidtijpiis tmmittis Schedl. 197S. Entomologische Abhandlimgen Staatliches .Museum tiir Tierkunde in Dresden 41:309 (Holotvpe. male: Brasilien. Linliares. E. Santo; Naturliistorisches Musemn W'ien '. \rusiiiutiu/iiu/ Tlie male lioIotApes, cited aboxe, of Platypus abditus Schedl lukI of F. transitus Schedl were compared by me directly to one another and to other representatiyes of this species. Because distinguishing characters could not be found, the junior name, transitus, is placed in smioii- > ni\, as indicated aboxe. Plat 1/ pus rusifnuis Sc-hedl. 1933. Ke\istade Entomologia. Sao Paulo 3: i73 ( I lolotxpe. male; Brazil, S. Paulo. .Ylto da Serra; Naturliistorisches .Museum W'ien) Platijpus pniiosHs Scliedl. 1961, Pan-Paciiic Entomologist 37:233 (Holohpe, m;ile; Venezuela, Mt. IDuitla; Califor- nia .Acadenn of Science. San Francisco). Scic sijnon\jm[i The male holot\pe of Platypus ntj)hilijj)iis ntulfiporns Schedl Treptoplatijpns initltiponis Schedl, 196S, Pacilic lust'cts 10:270 (Ilolotvpe. f'rmale; Okapa (kasa), E. lliglilands District [XewGuincal: CSIHO. Canberra) Plali/ptis fdstiumis ScliecU. 1969. Linneiui Society of New South Wales. I'roceedings 94:226 (Holot\pe, male; New Cuinea: Maral'unpi, 2S00 in: CSIRO, Canherra). \\-w SljIIOIII/lltll Schedl named Tn'ptoplati/piis nuilfiponis, cited above, from the female and Plati/piis jastiiosns, cited above, from the male. Subse- quent collecting has demonstrated that these names represent the opposite sexes cjf the same species. A note in his collection indicates that Schedl was aware of this problem. Both holo- t\pes, as well as additional material, were exam- ined. The jnnior name, fastiiosiis, is placed in .s\-nom ni\ as indicated above. Received 3 March 1992 Accepted 13 March 1992 Cicat Basin Xatnialist 52(1 ). 1992. p. 9o BOOK REVIEW Plant biolog\ of the Basin and Range. C. B. Osmond, L. F. Fitelka, and (;. M. IIid\. Springer-\erlag. BtM-lin, 1990. 375 p]). $69.50. This iiitriiLj;uiiianyon be declared a Research Natural Area described the can\-on as ". . . a hviu"; nuiseum and biological libraiv of a size that exists nowhere else in the Great Basin ... an invaluable bench mark in ecological time." The Red Butte Canyon RNA is unique becau.se it is a relativeK' undisturbed watershed adjacent to a major metropolitan area (Salt Lake \ alley). To protect this \aluable re.source, access to the Red Butte Canyon RNA has been largely restricted to .scientific investigators. One of the ,Depiirtnieiit iit Binlcirx . Uiiiveisitv of L't.ili. S.ill l„ike- Cil\. Ut.ili S41 12. "CoiiMilting irt-nloyisl, 1064 E. HilNneu Dnve , Salt L.ifce (iin. Ut.ili S4124. 95 96 Great Basin Naturalist [Volume 52 Salt Lake City ^^^^^^^^^^' Intl. Airport y////////. lie f//////////////////////////////y///////y//////y/yy/y//// Pinecrest CO o CD CD i.:Ia».^ A»Ar^ f//y/y///////y/yy//yyyyyyyyy/yyyyyyyyyyyyyyyyyyyyyyyyyyy k Aill PrPGK ^' '/ — I Kilometers ///,/, ///fy/y/,y,yy/yyy/yy//y///yy////y/y/////''/y//////' Mil' ^" Fig. L Ijocation of Red Butte Ciinvon and other sites referred to in text. goals of the RNA Program is to protect and preserve a representative array of all significant natural ecosystems and their inherent processes as baseline areas. A second goal is to conduct research on ecological processes in these areas to learn more about the functioning of natural versus manipulated or disturbed ecosystems. Research activities in the Red Butte Canyon RNA are directed at both of these goals: under- standing basic ecological processes (physiologi- cal adaptation, drought adaptation, nutrient c\'cling, etc.) and also the impact of humans on our canyons through both airborne (air pollu- tion, acid rain, etc.) and land-related (grazing, human traffic, etc.) activities. The latter are conducted through comparison of Red Butte with other canyons along the Wasatch Range. In size. Red Butte Canyon is relatix elv small compared with other drainages along the Wasatch Front. The drainage basin covers an area of approximately 20.8 km" (5140 acres) (Fig. 2). The drainage arises on the east from a minor divide betvveen City Creek and Emigra- tion canyons and drains to the west. The canyon has two main forks (Knowltons and Parleys) and many side canyons. Near the canvon base, a resen-oir was constructed earlier this century to prcAide a more stable water supply to Fort Douglas. The diversity of slope and aspect com- binations of the terrain contributes to a variet)' of biotic commimities along an elevation gradi- ent from about 1530 m (5020 ft) on the west end to more than 2510 m (8235 ft) at the crest. The puipose of this paper is to provide a brief description of the histoiy, flora, geology, cli- mate, and ecology of this unusual and valuable resource. There is increasing interest in Red Butte Canyon, in part by scientific investigators because of its utility as a protected, undisturbed watershed, and in part by curious citizens from the nearby Siilt Lake Valley. Yet, there has not been an overall reference available for those interested in general features of the canyon or past ecological studies within the canyon. Most of the information on Red Butte Canyon is scattered. With the closure of Fort Douglas in 1 99 1 , many of the historical records will become more difficult to access. It is hoped that the synthesis presented in this paper will provide the necessary background for those interested in the histoiy and ecologv of the Red Butte Canyon RNA. Irving McNulty first summarizes the history of the canyon, followed by Ted Amow's description of geologv' and soils. James Ehleringer contributed the h)'drology, climate, and plant ecology sections. The section on vas- cular flora was prepared by Lois Amow, and Norman Negus wrote the mammalian and avian fauna sections. 19921 Rkd Butte Canyon Heskahch Natural Area 97 <^ . /O .x^P^ 'Vo- ^0' 1^^ ^&- .^^ \^-® a^ .6^^. Q ,^ %3: 9.e' se^ ^o^^ ^vgS <^': .^^. O. ,Q Q ^.: 0 0 mile kilometers Fig. 2 Major drainages and weather and bench mark stations within the Red Butte Canyon Research Natinal Area. B represents the location of the USGS Bench Mark station; circles numbers 2, 4, and fi represent the locations ot weather stations known as Red Butte #2, Red Butte #4, and Red Butte #6, respecti\el\ . History The historv' oi Red Butte Can>oii comes as bits and pieces from many sources, including Arrington and Alexander (1965), Hibbard ( 1980), and the Fort Douglas Army Engineers Office (1954), records of the Fort Douglas Museum, and discussions with C. G. Hibbard (Fort Doug- las historian) and Harold Shore (Fort Douglas water master oxerseeing Red Butte Canvon). It is primariK' a hist(nA' of human iiupact on the utilization of natural resources provided bv the canyon. Major resources were water from the stream and sandstone quarried for use in con- struction. Of minor importance were grazing and timber In 1848, just one year after the arrival of the first pioneers in Salt Lake Vallev, red sandstone was first quarried in the canyon to be used in construction in tlie building ot Salt Lake Git)'. It was the closest source of construc- tion-quaHt)' sandstone and was quarried for almost 100 years. This mining had considerable impact on the plant and animal life in the lower portion of the canyon. The major use of Red Butte Greek water was by the U.S. Army at Fort Douglas, which was establish(nl at the mouth of the canvon in 1862. This utilization of water outside the canxon had little effect on the canyon itself, as U.S. Army administrators worked over many years to protect the watershed and water qualit)'. In fact, protection has grown steadily since Fort Douglas was first established, and particularly since the canyon was acquired by the U.S. Forest Service in 1969 and declared to be a Research Natural Area. 98 Great Basin Naturalist [Volume 52 A M(jb Mdo Mdo Township IN. Range IE 23 see I ion 22 ) kilometers Fig. 3 Geologic map of Red Butte Canyon Researcli Natural Area. See Table 1 for a de.sc ription of abbreviations. Solid lines represent contacts l)ehveen torniations, dashed lines represent norniiil faults, and T-ditsJied lines represent the Black Mountain thnist fault. The transect A-A' is shown in cross section in Figure 4. Adapted from Marsell and Threet {I960) and Van Honi and CMttenden (19S7). Red Butte saudstoue (Nuggett Sandstone) was the first resource utilized from the canyon. Most sandstone was obtained from Quarr>- Canyon on the south side of the canyon, 4.4 km (2.9 mi) from the mouth of the canyon. Because of the proximit\- of Quarr)' Canyon to Salt Lake C]it\', sandstone was (juarried there from 1848 to the end of the centur\- by private companies and intermittently by the Army until 1940. This required a road in the bottom of the canyon and housing for workers. In 1889, 66 men and 38 oxen and horses lived at the canyon bottom, contributing considerable downstream pollu- tion to Red Butte Creek. In 1887 the U.S. Con- gress provided a railroad right-of-way to be built to the rock (|uarr\' to increase the amount of sandstone removed. Stream pollution caused by quarrying activity' brought many complaints from Fort Douglas and ultimately a court action in 1889, which required the Salt Lake Rock Company to control stream pollution and cease housing men and animals in the canyon. Red Butte Creek was used for irrigation by a few pioneers east of Salt Lake City in the early 185()s. When Fort Douglas was established in 1862, Armv personnel initially depended mostly on water from nearb\' springs. However, by 1875 Armv personnel constnicted two reseivoirs east of Fort Douglas and diverted water from Red Butte Creek to fill them. In response to the recurrent stream pollution problems caused by quarrying activities, the Territorv' District Court, in 1890, declared that the waters of Red Butte Creek were the sole propeiiy of the U.S. Army and under the jurisdiction of Fort Douglas. Also in 1890, the U.S. Congress passed a law to 1992] Red Butte Canyon Research Natural Area 99 Tablk 1. Description of geological formations in Red Butte Canvon. Cenozoic era, Quatemarv .s\steni. Holocene scries fa Fldod-jilriin iillin iiiiiL Sand. eohhK to silt\, dark gra\' at top: grading ilownuaril to medium to liglit gra\, sand\' to cohbK' gra\el; kxalK bouldeiA . fc En^iiwered fill. Selected earth material that has been eniplaced and compacted. Cenozoic era, Quateman^ and Tertiary systems, Holocene and Pleistocene series /g Allurial-fdii deposits. Boulder\' to claye\' silt, tlark gra\' to brown; rocks angular to subrounded. Id Landslide deposits. Composition similar to material npslope. Mesozoic era, Jurassic system Jtc Tain Creek Liiiwstoite. BrtnMiish gra\' ;uid pale gra\ to pale yellowish grav silt\- limestone, intercalated with greenish gray shale. Mesozoic era, Jurassic? and Triassic? systems JTii Su^et Saitdstone. Pale pinkish buff, fine- to medium- grained, well-sorted Siuidstone that weathers or;uige- brown. Massive outcrops form the ridge c;illed Red Butte. Mesozoic era, Triassic system Tail Ankareh Formation, upper member Reddish brown, reddish puqole, grayish red, or bright red shale, siltstone, and sandstone. Ta<^Ankareli Formation. Gatira Grit Member White to pale purple, thick-bedded, crossbedded, pebbK' quartzite. Forms a prominent wjiite ledge for long distances. Tatn Ankareh Format i(n}. Mahogany Meml)er Reddish brovyn, reddish purple, gravish red, or bright red sh;ile, siltstone, ;ind sandstone. Tt Thai/nes Formation. Medium to light gray, fossiliferous, locall) nodular limestone, limy siltstone, and sandstone. Tw Wood.side Shale. Cravish red, grayish purple, or liright red shale and siltstone. Paleozoic era, Permian system !'))(■ Park City Formation and related strata. Fossiliferous sandy limestone, calcareous sandstone, iuid a medial phosphatic shale tongue. Paleozoic era, Pennsylvanian system Ptv Weber Quartzite. PiJe tan to nearly white, fine- to uiedium-gr;uned, crossbedded (juartzite and medium gray to pale gray limestone. Pn Round Valley Limestone. Pale gra\- limestone with pale gray siltstone partings. Contiiins pale pinkish chert that forms irregular nodules. Paleozoic era, Mississippian system Mdo Doughnut Formation. Medium gray thin-bedded limestone with pods of dark gra\ to black chert and abundant brachiopods and brvozoa. A/g/; Great Blue Formation. Thick-bedded. localK clilT- forming, pale gray, fine-grained limestone. A//( Hnmbuo Formation. Alternating, tan-weathering. lim\ sandstone and limestone or dolomite. Md Deseret Limestone. Thick ledges of dolomite and lime- stone v\ith moderately abundant lenses and pods of dark chert. Paleozoic era P Paleozoic rocks, undifferentiated. protect the water .suppK oi P^ort Dougla.s. This hiw prevented any .sale of land in the eanxon or fnrther watershed development. In 1906 the U.S. Army built a dam on Red Butte Creek to -suppK- additional water for Fort Dougla.s. The present dam was constructed between 192S and 1930, and the reservoir provided water ibr Fort Douglas until its closure in 1991. There are no grazing records available lor Red Butte Canyon prior to 1909, by which time the United States had acquired title to most of the land in the canyon. Cottam and Evans (1945) reported evidence of some gulK' erosion occurring in the canyon prior to 1909 and assumed it was due to overgrazing. Although we lack quantitative data, there are a few isolated incidents indicating the occurrence of grazing, including an 1 854 report of a young man drowii- ing in a flash flood in Red Butte Canyon while herding animals. Over forty head of oxen used to haul sandstone from the quarrv in the late 1800s reiuained in the canyon during that time. In 1869 the War Department appointed a herder to control loose cattle gnizing on Fort Douglas and in the canyon. In 1890 three squat- ters had settled into the canyon, and their forty- head of cattle were grazing in the Parleys Fork area before being evicted. B\' 1909 the Armv had built a gate at the mouth of the canvon to control access, thus further protecting the watershed. Although this did not prevent occa- sional animals from wandering into the canvon from adjacent canyons, it did reduce both their numbers and their length of stav. Consequentlv, most of the canyon has not been grazed b\ cattle or sheep through most of this centur\. Portions of the upper reaches of the can\on were timbered. In 1848, when a road was built along the canyon bottom, it was reported that there was an abundance of timber suitabk^ for fence poles. Later The CJhmch of Jesus C'htist of Latter-day Saints built a bowen on Temple S(|uare in downtown Salt Lake ('its' in the ISoOs with wood obtaiiu^l from Table .Moinui (between Knowltons Fork and Beaver C>an\()n). In 1863 the Arm\ constructed 34 buildings at Fort Douglas from "timber hauled from the canyons," but there is no indication as to how much timber came from Red Butte Canyon. However, apparently not manv timber-size trees were available in the lower canyon as indicated by a pioneer who built a log cabin in the canyon. He stated he had to tra\el five miles up the 100 Ghkat Basin Naturalist [Volume 52 canvon to obtain enough logs iov the cabin in the early 1860s. There are no available records of fires that niav liave occurred in the canvon. In 1988 a fire from Emigration Canyon spread into the upper headwaters of Red Butte Creek before it was contained. The land was subsequently reseeded with native species bvthe U.S. Forest Service. Land ownership within the canyon changed several times during the late 1800s and early 1900s. Land occupied by Fort Douglas in 1862 was officialK' given to the U.S. Army in 1867 when President Johnson withdrew four square miles from public domain for the use of the Anny. However, this included only a small por- tion of the mouth of Red Butte Canyon. The Salt Lake Rock Company, which quarried most of the sandstone in the canyon, owned part of the canyon, and the Union Pacific Railroad Co. acquired four sections in the lower portions of the canyon in the 1860s. Smaller portions of the canyon were claimed by private indi\iduals under the Homestead Act of 1862. Such ckiims could be acquired easilv under this act, which was veiT liberal and required onl\' a small claim fee. Graduall)', between 1884 and 1909, through a combination of acts of Congress, exchanges of property, and outright purchases, Fort Douglas obtained title to most of the canyon b-\' 1896 and almost the entire canyon by 1909. Only three small parcels of a total of less than 90 hectares (—200 acres) are still privately o\Aiied today, and these are close to the margins of the canyon. In 1969 the U.S. Department of Defense relin- (juished ownership of Red Butte Canyon. The U.S. Forest Service is now responsible for these lands. The Forest Service recognized the natu- ral state of the area had been preseived through many years of closure to the public and desig- nated Red Butte Canyon a Research Natural Area in 1970. By definition such areas are tracts of land that liave not been stronglv impacted b\' human-related activities such as logging or graz- ing by domestic livestock. Tl un are permanently protected from devastation by humans so they may serve as reference areas for research and education. Red Butte Can\'on has sened as a research site for biologists for over fifty years and w ill continue to do so in the future. Public education about conservation and the need for the public to better understand the importance of Research Natural Areas are major concerns. Recently the Forest Service briefly opened the canyon to the general public. In 1987 the canyon was opened to the public in late spring for several days; this weekend opening attracted over 5000 visitors and led to a trampling on vegetation along the main road in the canyon. This opening was repeated in 1988 and attracted 1100 people. Currently the State Arboretum at the University of Uttili conducts natural history education classes (—10 individu- als per group) in the lower portions of the canyon. Limited deer hunting has been permit- ted by the Forest Service each fall, but the impact of the hunts is unknown. A Red Butte Steering Committee, consisting of representa- tives from the Forest Service, the University of Utali, and other government agencies con- cerned with preservation of natural areas, is involved in making decisions pertinent to the jurisdiction and management of the Red Butte Canvon Research Natural Area. The histoid of Red Butte Canyon, with the exception of the quari-)ing acti\it\' and some grazing in the past century, is largely a histon" of preservation. The U.S. Army at Fort Douglas was concerned with the protection of the water- shed and gradually acquired sufficient control to protect it. The U.S. Forest Service declared the entire canyon a Research Natural Area and thus insured its protection for the future as a bench mark of riparian and shrub ecosystems in the Intermountain West. Geology The rocks underl)ing Red Butte Canyon range in age from recent Holocene deposits of our time to Mississippian rocks that are about 360 million years old. Holocene and Pleistocene deposits are unconsolidated, consisting mostly of landslides or alluvium deposited by existing streams. Their aerial distribution is shovvai in Figiu'e 3, and a description of the deposits is given in Table 1. The older rocks range in age from Mississippian to )urassic, a span of about 220 million vears. The)' are all consolidated now, but originallv they were formed as deposits in oceans or inland seas or as sand dunes in an arid environment. No rocks representing the approximatelv 140 million vears between the end of Jurassic time and the Holocene are pres- ent in Red Butte CJanyon. Either they were never deposited or they have been eroded. The consolidated rocks in most parts of the lower walls of the canyon consist chiefly of shale, 1992] Red Butte Canyon Researchi Natural Area 2500 - 2000 - 1500 - 1000 - meters Fig. 4. Geologic cross section of Red Butte Canvon. Explanation as in Figure 3. Adapted from Van Horn and Crittendei (1987). with some gritt)' (juartzite and sandstone. The upper southeast-facing slopes consist mostly of limestone with some sandstone and limy shale. Tlie upper northwest-facing slopes are made up mostK' of sandstone with limestone and limy shale near the southeast divide. Figure 3 shows the distribution of the rocks in the canyon, and they are described in Table 1. The older consolidated rocks in the canyon generally dip toward the southeast (Fig. 4), and they form the northern flank of a large s\iicline whose axis trends toward the northeast and whose southern flank is in Mill Creek Canyon, about 6.5 km to the south. The rocks are cut by numerous normal faults that are part of the \\asatch fault zone, a lengthy fault zone that bounds the west face of the Wasatch Range for ahnost its entire length. Movement along these normal faults has resulted in horizontal dis- placement of the rock formations, whereas nio\'ement along the Black Mountain thrust fault in the northwestern part of the canyon has raised older rocks to a position o\erl\ing yovm- ger rocks. The faults and their effects on the consolidated rocks are shown in Figures 3 and 4. Soils bedrock. The distribution of the soils in the canyon is shown in Figure 5. The relationship of the soils to the bedrock is apparent by compar- ing Figure 5 with Figure 3, a geologic map of the canyon. The soils map (Fig. 5) was adapted from Woodward et al. (1974). Soils in Red Butte Canyon have been characterized as dominantly strongly sloping to ver)' steep and well drained. According to Bond ( 1979), most soils are neutnil to sliglitK basic, xarv' in color from brick red to dark browni, with textures generalK- ranging from sandy to loamy clays. Depth of the soil is irregular, with depth to bedrock varying from nearly 2.4 m (94 in) at the canyon floor near the mouth to as little as 60 cm (24 in) or less on the slopes. Soil tvpes include loams, silt loams, and dry loams. There is little profile development, but a pronoimced litter layer and appreciable incorporated humus exist in places. CJeneralh' the soils are approximately 1 m (39 in) deep, especially those adjacent to streams. However, the steep, rocky upper slopes have shallow and cobbl\- soils. Table 2 includes a description of each of the soils shown in Figure 5. The descrip- tions were ackpted from Woodwiuxl et al. ( 1974). Hydrology and Nutrient Flow Soils in Red Butte Canyon are derived from Red Butte Creek is a perennial third-order the weathering and erosion of the underKing stream without upstream regulation or dixersion 102 Great Basin Naturalist [Volume 52 Township IN. Range IE 23 suction 22 kilometers Fig. 5. Soils map of Red Butte Canvon. See Table 2 for a description of abbre\iations. Adapted from Woodward et ;J. (1974). vintil flow is collected in the reservoir located near the base of the canyon. The stream has creatcnl a narrow-based canvon with sides rising abniptly at an average slope of about 35 degrees to the north and about 40 degrees to the south. Immediately upstream of the reserxoir is a U.S. Geological Survey Hvdrologic Bench Mark Sta- tion. This gaging station has been maintained b\ the U.S. Geological Survey since October 1963. Priortothat, the Corps of Engineers, U.S. Armv, recorded monthly discharge at this location beginning in Januarv 1942. The average monthly discharge (1964-88) is 0.133 mVsec (~4.7 ftVsec) as it enters the res- en'oir at 1646 m (5400 ft) elevation (U.S. Geo- logical Suivcy records). The stream flow exliibits a straightforward annual pattern, char- acteristic of this geographic region — high spring flows driven by snowmelt followed by very much reduced flows derived from groundwater throughout the remainder of the vear (Fig. 6). Spring melt flow, which is t\pically an order of magnitude greater than other periods of the year, peaks in Ma\- and persists for 6-8 weeks. The average monthlv stream flow rate during May is 0.416 mVsec (14.7 ftVsec). By Septem- ber, the lowest average monthly flow rate, stream discharge has decreased to 0.058 mVsec (2.0 ftVsec). Mean stream flow rates do not increase durino; the summer months, althouo:h nearly one-fourth of the annual precipitation falls during this period. Average monthly stream flow \alues, how- ever, hide much of the stream dynamics and resultant impact on riparian vegetation. On a daily basis, stream flows can vary tremendously 1992] Red Butte Canyon Research Natiral Area 103 Tablk 2. Description ol units on the soils map ol Red Butte C]an\on. AGG Agassiz association, ver\ steep. 40-7U percent slopes; nioderateK permeable, well drained. Agassiz — .35 percent, verv col)bl\ silt loam on ridges and convex areas of upper slopes. Picaviine — 55 percent, nonc;ilc;ireous variant, gravelly loam in concave areas tuid in draws. Other soils — 10 percent. BCG Brad ver\' rocIv\' loamy sand, 40 to SO percent slopes. \('i"\ [X'rmeahle, extremelv well drained. \en rocla, cohhlv. loamv sand; dark retklisli-hrowii; shallow. BEG Bradshaw-Agassiz association, steep. 40-70 per- cent slopes; moderatelv permeable, well drained. Bradshaw — .55 percent, very cobblv silt-loam in slightlv concave areas. Agiissiz — 3.5 percent, v erv cobblv silt-loam in convex areas and ridgetops where soil is shallow. Other soils — 10 percent. DGG Deer Creek-Picayoine association, steep. 30-60 percent slopes; nioderateK permeable, well tlrained. Deer Creek — .55 percent; loam; verv dark brown; deep on very steep, north- and northeast-facing mountain slopes. PicavTine — 35 percent; gravelly clav loam; verv dark brown, deep, calcareous on west-facing slopes. Other soils — 10 percent. EMG Emigration very cobbly loam, 40 to 70 percent slopes. Moderatelv permeable, well drained. Cobblv loam; facing south; dark, gravish brown; shtJlow; patches ot bedrock. HGG Harkers-VV'allsburg association, steep. .Moder- ately permeable, well drained. Harkers — .55 percent, loam, 6—40 percent slopes, ver\' dark browTi, deep in drainageways and concave areas of slope faces. Walls- burg — 35 percent, very cobbly loam, .30-70 percent slopes, on ridges luid convex areas of slopes where bed- rock is near the surface, verv dark gravish browii, shallow. Other soils — 10 percent. HHF Harkers soils, 6 to 40 percent slopes. .Vlotleratelv permeable, well drained. Loam and cobbly loam, on sloping old alhiviiil ftuis and steep mountain slopes. LSG Lucky Star gravelly loam, 40 to 60 percent slopes. Moderately permeable, well diiiinetl. Wrv dark gravish brown, deep on northerly slpes. Mu Mixed allu\ial land. PoorK drained, highly stratified mi.xed alhiviiini on undulating, gently sloping, and nearly level flood iihiiiis. during snowinelt, depending on air tempera- tures and sncmpack depth (priuiaril\- tliat of" upper Red Butte Canyon and Knowltons Fork). The 1982-(S.3 winter was one of unusually high precipitation along the Wasatch Front. Heavy snows in mid- May 1983 were followed b\- equall)- unusual wann temperatures at the end of the month. As a consequence, stream flow rates peaked at record \'alues. On 28 May 1983, Red Butte Creek crested at a discharge rate exceeding 2.97 mVsec (104.9 ftVsec) (stream flow was above the maximum gage height), and (nerland flow was substantial. This was !)\ far the greatest discharge rate in recent times, having eclipsed the previous maximum single day rate of 1.70 m^/sec (60.0 ftVsec) measured on 18 May 197.5 (U.S. Ceological Survey Records). The unusually high stream discharge rate in May 1983 is of particular significance because of its impact on stream geonioq)holog\- and adjacent vegetation. The high flows (juickly scoured the streambed, taking out beaver dams, eroding stream banks, knocking down riparian trees, and causing massive erosion. Gullies .5-10 m (16-33 ft) deep were cut into permanent streambeds in Knowltons Fork and throughout Red Butte Creek. Sediment flow associated with this record stream discharge was in excess of 269 metric tons (~.593.(){)0 lbs) per day in mid-Mav (compared to tvpical spring melt con- centrations of 1 metric ton [—2200 lbs] per day) (U.S. Geological Survey Records); this resulted in a delta formation at the mouth of Red Butte Resenoir Prior to the 1982-83 winter, no delta had existed. The delta was soon ~30 m (-100 ft) long. By 1990 the delta had fanned out more than 60 m into the reservoir The heaw winter rains of 1982-83 saturated soils all along the Wasatch Front, and landslides were common. Red Butte Canyon was no exception. Slope sloughing, which killed the overlying perennial vegetation, was common throughout the canvon. No doubt this compounded the stream sedi- ment load during the spring of 1983 and tor several years thereafter. In 1990 signs of the 1982-83 slope sloughing were still clearlv obvi- ous in Knowltons Fork as well as in the upper and lower portions of the main canyon. Natunil revegetation of both riparian and slope vegeta- tion t)pes has occurred since these floods. In particular, Acer neffimlo (boxelder) and Salix cxiffia (willow) have increa.sed in frecjuencv in the nevvlv deposited alluvium along the stream- sides (Donovan and Ehleringer 1991). Recov- erv of the sloughed slopes, which were for the most part covered bv/\.<^m/i<'//V/<7jfr/ff///i (bigtooth maple) and Qticrats ^amhclii ((»ambel oak), has proceeded at a slower rate, with those slopes still dominated by herbaceous species. As part of the bench mark analysis, the U.S. Geological Sunev monitors .several major iLSj^ects of stream qualitv in addition to stream discharge, including water temperature, suspended sedi- ment, and chemical qualit)'. Included with chemical rjualitv are specific conductance. pH. 104 Great Basin Naturalist "1.50 I I ' I ' 1 [Volume 52 C/5 CO 1.25 E (D 1.00 C5^ \- CO JZ 0.75 o C/5 "a E 0.50 03 0 C/D 0.25 Fig. 6 Mean monthly discharge rates of Red Butte Creek just before it enters Red Butte Reser\'oir. Large and small tick marks indicate end-of-year and mid-year points, respectively. Data are from U.S. Geological Survey records. di.s.soK'ed oxygen concentration, coliform bacte- ria, and ionic and dissolved elemental concen- trations (ammonium, arsenic, beryllium, cadmium, calcium, carbonate, chloride, chromium, cobalt, copper, fluoride, iron, lead, lithium, magnesium, manganese, mercury, molybdenum, nickel, nitrate, nitrite, phosphate, potassium, selenium, silver, sodium, sulfate, strontium, vanadium, and zinc). The stream itself is strongly alkaline (pH 8.0-8.6), and travertine is deposited at sev- enil points along the stream channel (Bond 1979). Summertime stream flow represents groundwater discharge, while the spring flows result primarily from snowmelt at higher eleva- tions. Not all of the grovmdwater originatine; from upper-elevation sources enters the stream before it leaves the canyon. Tracing the possible sources of water into stream, and therefore that water which is a\ailal)le to plants, is possible bv analyzing the isotonic composition of that water. The deuterium ("H or D) to hydrogen (^H) ratios of stream waters have been measured since June 1988 at the USGS Bench Mark sta- tion and at the mouth of Parievs Fork by the Stable Isotope Ratio Facility for Environmental Research at the University of Utiili (Dawson and Ehleringer 1991). These naturally occurring stable isotopes of hydrogen provide long-term data that are usehil in addressiu"; both Ions- term regional climatic patterns and the .specific water sources used by plants for growth (see discussion below). Hydrogen isotope ratios (ratio of D/H of a sample to that of a standard) are measured relative to an ocean water stan- dard; samples lighter than ocean water have less deuterium and are therefore negative in their values. Over the four-year measurement period (1988-91), hydrogen isotope ratios of stream waters have averaged near -122%o, with the only seasonal changes being more negative viilues occurring during spring snowmelt. Typi- cally the hydrogen isotope ratio of winter stonn events (snow) is more negative than that of summer storms. The hydrogen isotope ratios of wells and springs near Pinecrest (immediatelv east of Red Butte Canyon) are - 132%p, slightly more negative than Red Butte Creek (Dawson and Ehleringer 1991), and suggest that a frac- tion of the groundwater originating from the upper portions of the canyon may persist as underflow and does not enter the creek before leaving the watershed. Hely et al. (1971) indi- cated that substantial fracturing occurs in the bedrock of Red Butte Canyon, which would have the effect of increasing groundwater loss from the canyon through these layers and not \'ia stream discharge. Bond (1977, 1979) investigated nutrient- concentration patterns of stream flow in Red Butte Creek. In particular, his studies focused 19921 Red Butte Canyon Research Natuiul Area 105 Tablf. 3. Locations of wcatlicr stations of Red Butte C^iuivon. All stations were operattd 1>\ tlie U.S. Arniv between 1942 and 1964, and onI\- precipitation was recorded. The U.S. Geoloijical Siir\e\ has maintained a storage gage at Red Bntte #2 since 1964. The BioIog\ Department at the Universit)' of Ut;ili has maintained daik temperature, humidity, and wind speed records at Red Butte #2, Red Butte #4, iuid Red Butte #6 since 1982. Red Butte #1 . while technicall\ outside the canyon, forms an integrated part of the weather station complex. Station Location Latitude Longitude Elevation Period Red Butte #1 Fort Douglas 40° 46' Relocated to Biolog)' 40° 46' Experimental Garden Red Butte #2 Head of Red Butte 40° 47' Resenoir Retl Butte #3 Along Red Butte Creek 40° 48' at Brtish B;isin Red Butte #4 Along Red Butte Creek 40° 48' 100 m west of Bea\'er Canvon Red Butti- #5 Parleys Fork 100 m above 40° 47' inlet to Red Butte Creek Red Butte #6 Upper end Knowltons Fork; 40° 49' relocated to top of Elk Fork 40° 49' 110° '50' 110° .50' IIP 48' 111° 47' iir 46' 111° 48' 111° 45' 111° 46' 1497 111 1515 in 1653 111 lS65m lS90ni 17.53 111 2195 m 2195 m 1942-1964 1991-pre.sent 1942-19fS4 1982-present 1942-1952 1942-1971 1982-preseiit 1942-1956 1946-1971 1982-present on relationships between ntitiient transport out of the watershed and stream diseharge rates. Sokite concentration was not necessarilv pro- portional to stream discharge. Instead, for many ions, such as magnesium, sulfate, and chloride, the relationship was logarithmic. The slopes of these relationships depend on whether stream flow is increasing (i.e., spring snowmelt) or decreasing. Over the course of the year, a loop or directioucil trajectory was formed by having two different slopes. For most of the major ions, the trajectorv' was clockwise; that is, ionic con- c(Mitration was greater in winter when flow rates were low than during summer. Plant growth of the dominant riparian species commences near the end of the snowmelt period, and it is ques- tionable whether riparian species are able to utilize the greater nutrient aviiilabilitv durino; the snowmelt period. After snowmelt, stream discharge is based primarily on groundwater input. Nitrate, ammonium, and phosphate con- centrations in Red Butte Creek during ground- water discharge are low (Bond 1979). In contrast, overall concentrations of calcium, magnesium, sodium, chloride, and sulfate are much greater because of parent bedrock char- acteristics. Climate Climate within Red Butte Can\on is charac- terized by hot, dry summers and long, cold winters. Most precipitation occurs in winter and spring, with the summer rains less predictable and dependent on the extent to which mon- soonal systems penetrate into northern Utah. Mean annual precipitation ranges from about 500 mm (20 in) at the lower ele\ation to appro.x- imatelv 900 mm (35 in) at the higher elexations (Hely et al. 1971, Bond 1977; Table 3). Precipitation stations have been monitored in Red Butte Canvon by several groups. The U.S. Army had six rain gages in operation between 1942 and 1964 (Table 3). Bond (1977) collected data at several of these stations between 1972 and 1974. In addition, the U.S. Geological Sune\' maintained storage gages at Red Butte #2, Red Butte #4, and Red Butte #6 between 1964 and 1974. Since that time, they have maintained a storage gage at Red Butte #2. Within the watershed, diiiK' precipitation as rainfall is collected at eacli of the weather sta- tions; snowfall is not adequately measured by the sensors in place. However, these data are currently collected at Hogle Zoo in Salt Lake City (same elexation as pre\ious Red Butte #1, but 4 km south). Variation in annual precipitation w ithin Red Butte CJanxon is strongly dependent on eleva- tion (Fig. 7). The slope of this relationship is similar to that obser\ed for other mountainous areas within the Great Basin (Houghton 1969), and precipitation at the Salt Lake Cit\' reporting station (Salt Lake Citv International Airport) falls on this relationship. Thus, while lacking continuous precipitatif)n records for the canyon proper, precipitation records a\ailable for Salt Lake City can be used as a preliminar\- basis for estimating mean annual precipitation at differ- ent locations within the canxon. 106 Great Basin Naturalist [Volume 52 o 400 1200 1400 1600 1800 2000 2200 Elevation, m Fig. 7. Relationship between mean annual precipitation and elevation for Red Butte Canyon storage gages Red Butte #l-#6. Shown also is the mean annn;il precipitation for the primarv station of Salt Lake City (Salt L;iJpical for mid-latitude sites ha\ing onK' moderate cloud cover and little sunuiier precipitation. This number is quite useful not only in estimating the available photon flux for photos)Tithesis, but iilso in pro- \iding an estimate of the extent of solar heating of the surface, which ultimatelv affects air tem- peratures. Elevation has a limited impact on the PAR values within Red Butte Canyon, since the difference in elevation is relatively small. How- ever, we suspect there may be relatively large differences in PAR betv\'een Red Butte Can)'on and Salt Lake Cit\' because of increased mv pollutants within the city that tend to reflect the sunlight before it strikes the earth's surface. Most notablv we would see this as haze or smog within the \alle\' that is lacking once in the canyon. Average monthly atmospheric vapor pres- sure at site #2 showed little annual variation, ranging onlv about 3 nibar throughout the year (Fig. 8). Other sites exhibited a similar pattern. This parameter is largel)- affected by large air mass movements; and since subtropical air masses do not move into this region during the summer, the monthly changes in atmospheric \'apor pressure change little during the course of the year. However, because of the large annual change in air temperature and the non- linear dependence of the evaporative gradient on temperature, relative humidit\' levels are substantially lower and evaporative gradients are substantially higher during the summer months. Vascular Flora From the mouth of Red Butte Canyon at about 1530 m (5020 ft), its walls rise to their highest point— 2510 m (8235 ft)— at the head ofKnowltons Fork in the northeast corner of the canyon. Within this modest rise of 980 m (3215 ft) occur four distinct plant communities: ripar- ian, grass-forb, oak-maple, and coniferous. Piiion-juniper and ponderosa pine communi- ties, which often occur in this ele\ational range in Utah (Daubenmire 1943), are not present in Red Butte Canyon. Billings (1951, 1990), in discussions of vegetationtil zonation in the Great Basin, cites a greater incidence of winter cyclonic storms and slightly more moist sum- mers as factors producing the xariatioii in the vegetative zones of the eastern boundary' of the Great Basin. Juniper is present in the central Wasatch Range, i)ut onlv three Utah juniper ijunipenis osteospenmi) are known to exist in Red Butte Canyon: a mature tree with a 0.5 m (1.6 ft) diameter trunk, located on the south slope of Parleys Fork and nearly obscured by the more mesoph\tic vegetation, and two shniblike plants 1-1 .3 m (3-4 ft) tall growing on the south- west divide. With few exceptions, notably the naturalized grasses Agrostis stolonifera (redtop bentgrass), Bromits tectonim (cheatgrass), and Poa praten- sis (Kentucky bluegrass), onK the most common indigenous plants that occur in the \arious plant communities are listed below, primarily because the presence of introduced plants is usually dependent on disturbance and tends to fluctu- ate accordingly. Some of the more frequently occurring introduced plants are listed in a sep- arate section. Riparian community— From the point at which Red Butte Creek emerges from the canyon and throughout the floor of the cam on the streamside vegetation (plants residing in soil kept moist to wet by the stream) consists chiefly of western water birch (Bettila occidcntalis) and mountain alder {Aliuts incana), accompanied at intervals by usuiilly dense stands of red osier dogwood {Corrms sericea) and willow {Salix spp.). Adjoining the stream along the floor of the canyon below and above the reservoir is an often densely wooded strip consisting chiefly of Gambel oak {Quercus gambelii), boxelder {Acer ncgiindo), and bigtooth maple {Acer grancli- dentatinn), many of these trees ranging from 9 to 18 m (30 to 60 ft) or more tall. Also included in this plant connnunit} are wideK scattered individuals or small populations of cottonwoods {Populns frenwntii, P. angustifoUn, and P. x acuminata), chokecherry {Pniniis virginiana). Woods rose {Rosa woodsii), bearbern,- honey- suckle {Lonicera invulucrata), thimbleberry {Rubus parvifloms), serviceberry {Amelanchier ainifolia), western black currant {Rihes htid- soniamini), and golden currant [Ribes aurenin). Relatively few species of grass and forbs are found here, among them: Ehjitms i>l(innis Loiiuitiitin (iLsscctiim Mahouia refjens ( B c rb c n.s ref)e ns) Osmorhiza chilemis Poa comprcssa blue wildrv'e y;iant lomatium Oregon grape sweet cicelv Canada bluegrass 108 Great Basin Naturalist [Volume 52 P. pratensis Kentucky hliiegiiiss Smilacina stellata wild lily-of-the-valley S. raccinosd false Solomon-seal Solidago canadensis goldenrod Bcaven once native, were reintroduced into Red Butte Canyon in 1928 (Bates 1963) and were active along Red Butte Creek and some of its tributaries for 54 years thereafter. Numerous marshy areas between elevations of 1645 m (5400 ft) and 2133 m (7000 ft) were created by the impoundment of water due to their dam- building activities. To prevent the beaver popu- lations from becoming undesirably large, the Utiili Dixision of Wildlife Resources in 1971 undertook management of the populations. In December 1981 a recommendation was made, based on an analysis of the water supply to Fort Douglas from Red Butte Canyon, that all beaver be eliminated from the canyon because their feces could contaminate the water with the par- asite Giardia Jamhlia. Accordingly, in 1982 the colonel in command of Fort Douglas applied for and received from the Utah Division of Wildlife Resources a permit to remove the beaver from the canyon. Subsequently, all beaver were "har- vested." Bates (1963) studied the impact of beaver on stream flow in Red Butte Canyon. The vegeta- tive cover was affected for approximately 91 m (298 ft) on either side of the portion of the stream in which the beaver were active, and sediment deposited behind the beaver dams in the canyon varied from 0.6 to 2.4 m (2 to 8 ft) in depth. He also noted that the small alluxial plains formed by the sediment made it apparent that during periods of high rimoff, and perhaps during normal flow, the dams allowed the reten- tion of quantities of suspended materials. Schef- fer (1938), in a report on beaver as upstream engineers, ascertained that two beaver dams retained 4468 m' (157,786 ft^) of silt. It is not known whether an actual count of the number of beaver dams in Red Butte Canyon was ever made; but the environmental change effected by their ultimate displacement during the 1983 flooding of what had to have been enormous quantities of sediment has been significant. The removal of all inactive beaver dams has inevita- bly led to the elimination of or significant reduc- tion in the densitv' of some 55 species of t^'^iicalK wetland plants from once marshy areas wdthin Red Butte Canyon. For example, in 1990 it was noted that in an area which once supported a nearly pure stand of closely spaced cattails {Typha Idtifolia) covering approximately 0.25 hectare (0.62 acre), only a few scattered clumps remained. According to Forest Service person- nel, these losses would not have been as severe had the beaver dams been active during flood- ing. Species in the following genera are among those undoubtedly affected: Eleocharis, Scir- pus,Junnis, Arhiza macrophijlla Bal.samorhiza sagittata Bromns teetoniin Cirsium undulatiim CoUomid linearis Comandra innhellata milfoil Narrow tapertip onion western ragweed Holhoell rockcress pnr][ile threeawn Louisiana wormwood Utah milkvetch everywhere aster cutleaf balsamroot arrowleaf biilsamroot cheatgrass gray thistle narrowleaf collomia bastiird toadflax 1992] Red Buttk Canyon Research Natural Area 109 niomitain li auks heard loiiji-stalk spriiig-parslev sleiulcr wlu'at grass aiituinii willowherh spreading ckisN' broom siiiikeweed northern sweetvetch showy goldeneye temate lomatiuin silveiT Kipine little polecat threadleat scorpionweed longle;if phlox Sandberg bhiegrass needle-and-thread mnlesears Crepls (icuininatd Cynioptents lon^ipes Ely mils traclii/caiiliis {Ai^ropyron caiiinuin) Epih >l>i uin h rack ycarjnim (E. panicuhtum) Erigeron diveraens GuticiTczUi sarothrae Hcclysani in horcale Helionwris mitltiflora ( V'(g(»V'ra niiiltifliira ) Lonuitium tritenuituin Lupinus argenteiis Microsti'ri.s gracilis Phacelia linearis Phlox longifolia Poa scninda [P. sandhcrgii) Stipa conuita Wt/ctliia ainplcxicaidis Oak-MAPLE communit\'. — Gambel oak {Querciis gamhelii) is the dominant type of veg- etation tliroughoiit the altitudiniil range of the canvon. It forms what appear to be randomly spaced clones throughout much of the area. In accordance with the moisture regimen, the clones may range from thickets 0.3 m (1 ft) or less in height in dr\' upland sites to stands of stately, well-spaced trees in lowland areas. Both walls of the canyon support often nearly impenetrable oak in association with bigtooth maple {Acer grand identatiun) , the latter grow- ing chiefly in drainageways. Few species thrive as understor\' with dense oak cover. The most common are Galium aparine (catchweed bed- straw) and Mahonia repens (Oregon grape). Others appearing seasonally under oak are Enjthroniiim grandiflonim (dogtooth violet), Claijtonia lanceolata (lanceleaf spring beauty), Hydroplujllum capitatum (ballhead waterleaf), and H. occidentale (western waterleaf). Among plants commonly fringing oak clones are: Agoseris glaura mountain dandelion Apocyniun androsacinifolinin spreading tlogb;xne Arabis glabra tower mustard Bromus carinatus mountain bronie Comaiidra itmbellata bastiird toadflitx Delphiniinn niittallianinn Nelson larkspur Descurainia pinnata blue tansv nuistard Eriogunum heracleoides whorled buck-wheat E. racenwsiim redroot buckwheat Geranium viscosissimum sticky geriuiinm Hcliandiella unijlora one-headed sunflower Heliomeris multiflora (Vigiiiera multiflora) hairv' goldeneye Hydrophyllum spp. waterleaf Koeleria iiuierantha (K cristata) Junegrass Leucopoa kingii (Hesperochloa kingii) spike fescue Lomatium dissectiim giant lomatium Machacrantlicra canescens hoar\' ;ister Meiiensia brei isti/la Microseri.s nutans Pha celia heterophylla Poa fendleriana P. pratensis Senecio integcrrimiis Wasatch bluebell nodding scor/onella varileaf scoq:)ionweed muttongriiss Kentucky bluegrass Columbia groundsel Mountain mahoganv {Cercocarpus ledifo- litis) occurs as individuals and as scattered, mostly small populations, often in association with oak, sagebrusli, or other mountain shrubs, generally on northwest-facing, sparsely vege- tated slopes. It can be seen from the main road through the canyon as small trees against the sk\' along the exposed, rock-v, south rim of the canyon, especially toward its western end. As low shmbs it occurs sporadicalK; chiefl\' on exposed diy sites above 1980 m (6500 ft). Big sagebrush {Ariemisia trident ata) occurs sporadically in drier sites throughout the canyon's altitudinal ran^e. Low sao;ebrush (Artemisia arbnscula) occurs as relatixely pure stands at about 2133 m (7000 ft) along the southeast rim of the canyon. Coniferous community. — Douglas-fir {Pseudvtsuga menziesii), white fir (Abies con- color), and aspen (Popnlus trenmloides) domi- nate this community, either in pure or in mixed stands, growing chiefly on north- to northeast- and northwest-facing slopes; the aspen reach as low as 1706 m (5600 ft) and the firs occur mostly above 1828 m (6000 ft). Achlorophyllous CorallorJiiza spp. (coralroot orchid) are ainong the few plants able to flourish in the shade of dense stands of mixed conifers. Many small trees, shrubs, forbs, and grasses thrive in less dense stands or in openings between stands of trees in this commimit)'. Among them are: Aeerglabntm Anwianehier ainifolia Acjiiilegia eoendea Aniiea spp. Castilleja spp. Ccanothiis vcliitiniis Elymus glaueiis Erigeron speciosus Galium spp. Hordeum braeliyantlicntin Lathy nis paiieiflonts Physoca rjnis nuilvaceus Poa nervosa Pninus virginiana Rihes viscosissimum Riibus paniflora Sambncus spp. Sorbiis seopuliua Symphoricaiyos oreophilus Thalictniin fendlcri Rocky Mountain maple Saskatoon seniceberry Colorado columbine arnica Indian paint brush mountain lilac blue wildr\e shouy fleabane bedstraw meadow barley Utah .sweetpea mallow ninebark Wheeler bhiegrass chokecherrv' sticky currant thinibleberr\ elderberr) American mountain ash mountain snowberr\' FendJer meadownie 110 Great Basin Naturalist [Volume 52 Plants endemic to Utah. — Only two spe- cies occurring in Red Butte Canyon are said to be endemic to Utah: Ang^elica wheeleri Wats. (Mathias and Constance 1944-45) (Wheeler angelica) and Erifieron arcnarioidcs (D. C. Eat.) Gray (rock fleahane). Angelica icJieeleri has, however, been collected close to both the Idaho and the Nevada boinidaries with Utah (Albee et al. 1988). Ehgeron arciiaiiokles is kn(nvn from Salt Lake, Utah, Tooele, Weber, and Box Elder counties (Albee et al. 1988, Cronquist 1947). Plants introduced to Utah. — In Red Butte Canvon, plants introduced to Utali, either from other portions of the United States or from another country, are largely restricted to road- side and trailside sites and to open grassy or rocky slopes below 1829 m (6000 ft). Some of the more commonh' occurring plants in this categorv are: Ali/ssu in ahjssoulcs Artibiclopsis thaliana B ramus hriziformis (B. hrizacfomiis) B.Japonicits B. tctiontm Capsclla hu rsa-pastoris Ct/n()<^l().s.sum officinale Dactijlis t^loinvrata Draha vcrna Erodiuni cicutarium Grin deli a sqiia rrosa Holostcum iiinhcllafnin Isatis tinctoria Ladiica scrrioUi Lcpidiuin jx'iidliiitunt Linaria dahnatica Lithospcnnti nx ancnac Mdlva nc'^lcctd Mdilotus alha M. officinalis Poa Indhosd Ranunadiis tcsticiilatiis Sisijmhrinni altissiiinun Tanixdciim officiudle Thlaspi dncnsc Trdff)poan\'on ha\e been collected between an ele\ation of 1S2S and 2438 m (fiOOO and 8000 ft) in can\ons liaxing a greater altitudinal range in southern Salt Lake Countw This figure indicates tliat the Holistic di\ersit\' in Red Butte Cainon, while greater than that in hea\ih" disturbed Emigra- tion ('aiiNon (Cottani and E\ans 1945), is less than that in camons farther south. Nomenclatural changes since Arnow (1971) are listed in the Appendix. Plant E(;ol()(;y Vegetation distribution. — A number of studies ha\e focused on describing the \egeta- tion distribution within Red Butte Can)'on (Kleiner and Harper 1966, Swanson, Kleiner, and Haiper 1966. Kleiner 1967). There is a strong xeric to mesic elexation gradient, with lower portions of the canxon dominated b\- a spiing-actixe grassland communitx and the upper portions ol tlu^ cainon txpicaJK consisting oi suinmer-actix'e scrub oak, aspen, and conifer- ous forest cominunities (F'ig. 10). CJomposition within each of these communities is not con- stant, but instead species \an' in their impor- tance within a communitv t)pe as orientation and ele\ ation change. These elevation gradients n^present a continuum of moisture axailabilitx; with high temperatures and low precipitation amounts at lower elevations making conditions more xeric, while slope orientations less south- vv\\' in exposure become progressivelv more mesic within an elevation band. Soil txpe (Fig. 5) and depth also play a major role in afflicting plant distribution by providing variation in the water-holding capacity of the substrate. The dis- tribution of the sciTib-oak communitx- to the highest elevations within tlie canxon is most likelv related to soil conditions, sinc(^ at liigh elexations scrul) oak persists on south-, east-, and west-facing slopes that would normallv be expected to be dominated b\ aspen if it were not for the \en' shallow, rock^' soils that txpif\ these elex ations witliin Red Butte Ciinvon. Red Butte Canvon has been largeK pro- tected fr(jm grazing since its ac(juisition by the U.S. Army almost a centuiy ago. The conse- (juence of this lack of grazing pressure at lower elexations is a recoxerx' to near pristine levels, and this is clearly reflected in the earl\- commu- nitx- anaKses of Exans (1936) and Cottam and Exans (1945). \\'ithin the .scrub oak and grass- land communities of Red Butti^ Camoii and adjacent Emigration Can\-on, a canyon annually expo.sed to sheep griizing, there are large differ- ences in plant densitx' (Fig. 11). Emigration Canvon was originally described by early pio- neers as haxing a dense vegetation at lower elevations. However, grazing not onlv reduced that coxcr but also increa.sed the fraction of the plant cover occupied In- mderal, weedv .species (Cottani and Exans 1945). While plant densit)' in Red Butte Canyon mav be greater and weedy species composition loxx'er as a result of reduced disturbance and grazing, the canvon is not free of these vxeedx components and historical effects (as noted in earlv- sections). Dam con- struction during thi> 1 920s and other U.S. Army actixities vxithin the lower portions of Red Butte C^anxon have resulted in sufficient disturbance that main mderal, weedy species, such as Crindelia sijuarrosa (curlv gumvx'eed), Lactuca serriola (pricklv lettuce), and Polygonum avi- culare (knotxveed), are novx- common. 112 Great Basin Naturalist [Volume 52 Saniuelson (1950) conducted an analysis similar to that of Cottam and Evans (1945) on the algal components of the streams in Red Butte and Emigration canyons. He observed that as a result of livestock grcizing and human settlement, sediment load and turbidity were much greater in Emigration than in Red Butte Creek. The consef juence of this stream-qualitv difference was the dominance by algal genera in Emigration Creek that are turbidity tolerant, such as Oscillatoria and Phonnidium. Con- versely, in the clear waters of Red Butte Creek filamentous algae, primarily Nostoc, were most common. Overall algal densities were three times greater in Red Butte Creek, owing to the greater light penetration into that stream. At the same time, Whitney (1951) compared the dis- tributions of aquatic insects in the two streams. He found that densities of aquatic insects were greater in Red Butte Creek. Of those insects persisting in Emigration Creek, there was a preponderance of species characterized by gills protected from silt, which would better allow them to tolerate the more turbid conditions in Emigration Creek. Phenology, — Plant activity is governed by t^vo parameters: temperature and soil moisture availability. Cold winter temperatures limit growth activity between November and March (Caldwell 1985, Comstock and Ehleringer 1992). While a limited number of species, such as the early spring ephemeral Ranunculus tes- ticulatus (bur buttercup), may begin activity during warm periods in Eebmary, most annuals do not begin growth until the warm periods between snowstorms in early March. At lower elevations, a number of herbaceous perennials such as BalsainoHiiza macroplujUa (cutleaf balsamroot) may begin to leaf out during March, but most woody perennials do not leaf out until mid- to late April. The annvials and most herba- ceous species at lower elevations have com- pleted growth and reproduction by mid-June and then remain dormant until the following autumn or .spring (Smedley et al. 1991). In con- trast, woody species at lower elexations remain active from April through October, although the vast majority of the growth will occur during the spring (Donovan and Ehleringer 1991). At higher elevations, vegetative and reproductive growth are delayed imtil late May or June by cold temperatures. Plants at the higher eleva- tions vdll remain active throughout the summer, 30 r 20' ^ 10 m Red Butte n Emigration *i>.^ ■A 1515 1625 1700 Transect elevation, m 2060 Fig. IL A comparison of the plant cover in open grass- Ituid communitie.s of different elevations in Red Butte and Emigration ciinyons. Adapted from Cottam aiid Evans (1945). even though there may be httle summer precip- itation (Dina 1970, Dina and Khkoff 1973). Adaptation. — In the nonforested portions of the Intermountain West, plant growth is largely restricted to spring and early summer periods by cold temperatures during winter and limited water availabilitv during the summer (Caldwell 1985, Dobrowolski, Ciildwell, and Richards 1990, Comstock and Ehleringer 1992). A number of recent reviews have addressed adaptation characteristics ot plants growing in these environments (Caldwell 1985, DeLucia and Schlesinger 1990, Smith and Knapp 1990, Smith and Nowak 1990). For the most part, plants within Red Butte Can von are exposed to a hot, diy environment, with little relief from developing water stress during the summer months. The onlv clear exception to this pattern is the series of plants within the riparian com- munities cilong the canyon bottom. To giiin a better imderstanding of this occurrence, many of the recent ecological researchers within the Red Butte Canyon RNAhave focused on mech- anisms by which plant species have adapted to limited water availabilitv. Among the first ecophysiological studies was that b)' Dina ( 1970), who examined water stress levels of the dominant tree species in the lower portions of the canyon: Acer firandidcntatum (bigtooth maple), Acer negundo (boxelder), Artemisia tridentata (big sagebrush), Purshia tridentafa (bitterbrush), and Quercus ganibelii (Cambel oak). Dina (1970) observed that 1992] Red Butte Canyon Research Naturae Area 13 o E o E E >. o c o o CD en ZD I CO grasses forbs April May June Fig. 12. The mean water-use efficiency viilues for grasses and forbs within the grassland community of Red Bvitte Canyon during main period of the growing season. Water-use efficiencies were calculated from ctirbon isotope discrimination values from Smedlev et al. (1991) ;uid the \apor pressure data in Figure S. middav leaf water potentials of -30 to -65 bans develop in perennials occupying slope sites during late sunniier, whereas water potentials of adjacent riparian tree species are maintained between -20 and -30 bars during the same periods. Water potentials in the range of — 10 to -15 bars cause many crop species to wilt and close their stomata, reducing transpirational water loss. Tolerance of water stress le\els as low as -40 to -60 bars is thought to occur in only the most drought-adapted aridland species. These late-summer water potential \alues on slope species are sufficientK' low to close sto- mata and reduce photos) nthesis to near zero values. In Dina's (1970) study photosynthetic rates of riparian species decreased bv 50-80% from nonstress \alues, l)ut riparian trees were able to maintiiin positive net photosynthetic rates throughout the summer. More recentK; Dawson and Ehleringer (1992) and Donovan and Ehleringer (1991 ) conducted related stud- ies and again obsened that photos\iithetic carbon gain of slope species is largely limited to spring and early summer, whereas riparian spe- cies are able to maintain photosNuthetic rates throughout the \ear, albeit that photosxiithetic rates are lower in summer than in spring. Two common responses to limited water a\ailabilit> are axoidance and tolerance. Axoid- ance of water stress is accomplished by comple- tion of growth and reproductixt* activities before theon.set of thesunimer drought, whereas toler- ance is associated with the e\olution of features that allow plants to persist through the drought period. Several interesting studies ha\e been con- ducted in Red Butte Canyon that shed liglit onto the nature of a plants ability to tolerate water stress and persist through time. Treshow and Harper (1974) examined longevity of herba- ceous perennials in grass, mountain bmsh, aspen, and conifer communities throughout the canyon. They observed that life expectancies of dominant herbaceous perennial species, such as A.sf/7/gc////.s utahcnsis (Utah milk\etch), Balsa- niorliiza inacwpJu/lIa (cutleaf balsamroot), Hech/sanini horcale (northern sweetvetch), and WyctJiia ainplexicaulis (mulesears), are rela- tiveK' short (3-20 vears) when compared to the longer-li\ed (>65 years) grass species, such as Ag^ropyron spicatum (bluebunch wheatgrass) and Stipa comoto (needle-and-thread). The inabilitA- to persist through successive drought years ma\' be one of the reasons that dic()t\Ie- donous species have shorter life expectancies than monocotyledonous species. Related to this, Smedlev et al. (1991) examined the water-use efficiency of these and other herbaceous grass- land species. Water-use efficiency, the ratio of photosynthesis to transpiration, serves as a mea- sure of how much photosynthetic carbon gain occurs per unit water loss from the leaf. Dicot herbaceous perennials had consistently lower water-use efficiencies than their monocot coun- teq^arts (Fig. 12). The differences in intrinsic water-use ef^ficiencv within this life form maybe a major contributing factor to the shorter life expectanc) in dicot herlxiceous species. Consis- tent with this pattern, Smedley et al. (1991) observed that wat(^r-use efficienc\- of annual species is significantK' lower than that of peren- nial species in grasslands along the lower por- tions of the canyon. The\' also obsened that perennials which persist longer into the summer drought period have higher water-use efficien- cies than those species that became dormant in late spring. During 1988-90, precipitation was unusualK- low. The effects of the three-year drought are now seen in Canibel oak and bigtooth maple at their lower distribution limits, especialK- on shallow soils, where stem dieback has become pre\alent. 114 Great Basin Natuhalist [Volume 52 10 cm March April Fig. 13. Heiglit of Ci/iiuijiti'ni.s lunfiipcs ahoM^ tlic- u;ii)uik1 siiriace at differt- nt Afler'wVrketal. (19.S6)'. on til May urm\i till- .spriii- is to incnnise leaf angle, thereby rechicing incident solar radiatioji levels. In the grasslands on the lower portions of Red Butte Canyon is a most unusual plant spe- cies, Cijmopfcnis lon^ipes (long-stalk spring- parsley). Sometinu^s knowm as the "elevator plant," C. I()i}rbac(n)us perennial with an elongating pscudosca[)e (a scape is a leafless flowering stalk arising froiu ground level; the pseudoscape is an elongation of the leaf-bearing stem in the retnon between the roots and existing leaves). Other (-ijmoptcnis species also have a pseudoscap(\ but in none of the other species is it as well dexcloped as in C. loii^ijx's. In spring, solar heating of the ground surface increases soil and leal temperatures and can n^sult in moderateK' warm knif temperatures (3()-.35 (]). These tem- peratures are substantialK' higher than the opti- mimi photosvnthetic temperature for the eleva- tor plant and result in both a decreased photo,s\nthetic rate and a decreased water-use efficiencN' (Werk et al. 1986). To increase both the rate of photosvnthetic carbon gain and water-use efficiency, the pseudoscape elongates as spring temperatures progressiv^ely increase (Fig. 13). The result is that what was once a prostrate canopv is elevated abo\e the warm soil surface and now exposed to cooler air tempera- tures abo\e the ground surface. Werk et al. (1986) showed that the rate at which the psuedoscape elongates is dependent on the rate of soil-surface heating. Plants from protected or north-facing sites elongate less than those from exposed, southerly sites. Donovan and Ehleringer (1991) examined relationships between water use and the likeli- hood of establishment b\' common shnib and tree species in the lower portions of Red Butte Canyon. They obsen^ed that photosvnthesis is greater in seedlings than in adults throughout most of the growing season, but that water stress and water-use efficiencv' are lower in seedlings. Seedling mortalit\ in several of the species is associated with highei- water-u.se efficiencies, suggesting that mortalitv' seU^ction occurs with greater fr(H|uencv in seedlings that are conser- vative in their water use before tlun ha\ e estab- lished sufficiently deep roots to suni\ c the long stunmer drought period. Few studies have addressed ecophvsiologi- cal as])ects of riparian ecosvstems in the Inter- mouutain West. This is somewhat surprising since riparian ecos\ stems are most often among the first to be damaged bv human-related activ- ities, Irom outdoor recreation to water 1992] Ri<:n BuTTK Canyon Heseaiu:ii Natural Area 115 g c5 L_ (D Q. O O CO c 0 o ■D >^ X o CD 03 X -50 -70 -90 O -110 -130 ■150 -| r A ^'-E^' ■ D Acer grandidentatum • o Acer negundo A Quercus gambelii .a o precipitation stream water ground water .%",S^*^„%o^ ^ o oo J L J L 12.5 25 37.5 50 DBH of main tree trunk, cm Fig. 14. Hydrogen i.sotope ratio of stem waters ot tliree eoninion streainside luul adjacent nonstreaniside tree species in Parle\s Fork oi Red Butte Canvon as a function of the diameter at breast height ol the main tnuik. Plotted as gray bars are also the h\(b-ogen isotope ratios of the tluee possible water sources for these plants: local precipitation, stream water, and groundwater. Open symbols represent streamside phuits and closed symbols represent nonstreaniside plants. .Adapted Irom Dawson and EhlenniTer (1991). iiiH)()tin(lnient to grazing. Red Butte Canyon, a.s one of the few remaining riparian systems in the Intermountain West not severely impacted h\ hiiuuin actixities, is ideal for studies of the adap- tations of riparian plants and for comparatixe .studies of .species .sensitixities to human-related actixities. in a recent studx Daxxson and l^lileringer 1 1 992) examined xvater sources used by riparian plants species. In their study, plants xx'ere segre- gated according to microhabitat antl size: streamside xersus nonstreaniside and juxenile xersus adult (based on diameter at breast height). Their results xvere ratluM- startHng and suggest that a uexx' per.spectixe is necessan' xxhen exaluating riparian communities, their establishment potentials, and their sensitixitA' to disturbance. Dawson and Ehleringer (1991) used hydrogen isotope anah'ses of stem xxaters to determine the extent to xx'hich different cat- egories of riparian trees utilize stream xx'aler, recent precipitation, or groundxxater. I lydrogen isotopes are not fractionated b\' roots during xxater uptake; therefore, the hydrogen isotope ratios of stem xxater xxill reflect the xxater sources currently used by that plant. Rain, groundxxaters, and stream xvaters differ in their hxdrogeu isotope ratios, proxiding a signal dif- ference that could be detected bx' stem-xx'ater analxses. Daxx'son and Ehleringer (1991) obsei-xed tliat among matui(> tree species none xxere directlx using stream xx'ater (Fig. 14). All xx'(M-e using waters from a nuich greater depth, x\ Iiich had a hxdrogen isotope ratio more nega- tixc than either stream xxater or precipitation. Young streamside trees utilized stream xxater, but onlx when small. Young trees at nonstream- side locations utilized precipitation, haxing access to neither stream xxater nor deeper groundxxater. One possible reason that stream- side trees max not depend on stream xx'ater is that this surface xx-ater source ma\" occasionallx' drx up during extreme drought years and become unaxailablc^ to these trees; another is that stream chaimels occasionally change their course, and dependence on sinface moisture xx'ould then result in iiu-reased drought stress and likely increased uiortalitx" rates. The long- term stream dischariie rates suggest that stream 116 Great Basin Naturalist [Volume 52 water ma\' be less dependable than deeper groundwater sources (Fig. 6). Man\' plants do not contain both male and female reproductive structures in their flowers, but are present as either male or female plants (dioecy). Freeman et al. (1976, 1980) noted that dioecy is a common feature of plants in the Intermountain West. Furthermore, they obsened that the two sexes are usually not ran- domly distributed across the landscape. Rather there is a spatial segregation of the two sexes such that females tend to predominate in less stressful microsites (wetter, shadier, etc.), whereas males occur wdth greater frequencies on more stressful sites (drier, sunnier, saltier, etc.). In Red Butte Canyon, Freeman et al. (1976) investigated spatial distributions of Acer lu'f^iindo (boxelder, a riparian tree) and Thalic- tniDifeiulh'ti (Fendler meadowixie, a perennial herb). In both species, there was a strong spatial segregation of the two sexes. Dawson and Ehleringer (1992) have fol- lowed up on the initial obseivations of spatial segregationin Acer negimdo (boxelder), seeking to determine whether intrinsic physiological differences among the sexes may contribute to plant mortalit)' in different microsites. They observed that female trees have significantly lower water-use efficiencies than male trees on both streamside (where female predominate) and nonstreamside locations (where males pre- dominate). Male trees exhibit a higher water- use efficiency in drv sites than in streamside locations, but female trees exliibit no such response across microhabitats. The lack of a change in water-use efficiency b\' female trees on dr\', nonstreamside locations ma)- contribute to an increased mortality rate, which then ultimately results in a male-biased sex ratio at these .sites. Mammalian Fauna The mammalian fauna of R(^d Butte Canyon is remarkably diverse, due in part to the altitu- dinal gradient and mmierous small patches of various plant conununities indigenous to the area. A particularly rich small mammal fauna is associated with the patches of riparian habitat along Red Butte Creek and its tributaries. Prior to the iim-off of 1983, riparian habitats were much more extensivek dexeloped than at pres- ent. Numerous marshy meadows existed in association with large, actixe l)ea\er dams prior to 1982. The loss of acti\e beaxer dams in the early 1980s has doubtless greatly reduced the populations of small mammals that are restricted to the mesic-marshy habitats of the canyon. Nonetheless, based on the altitudinal gradi- ent and vegetational diversity of Red Butte Canyon, a total of 51 species of mammals should hyj^othetically occiu" there. Below is a list of the 39 species of mammals knowni to occur in Red Butte Canyon. I NSKCTIX'OKA — SOHICIDAE So rex palustris water shrew Sorex vagmns wandering shrew So rex cinereus masked shrew CHIROPTEKA — VESPERTILIONADAK Eptesiciis fuseiis Lagomorpha — Leporidae Lepiis townsendi StjJvilagus mittallii big brown bat white-tailed jaekrabbit Nuttall cottontail RODENTIA — SC1URID.\E Tainiascinnis liudsonicus red sfjuirrel Mannota flaviventer yellow-bellied marmot Speniiophihis annatus Uinta ground squirrel Spermophihis variegoftis rock squirrel Eutamias ininiinus least chipmunk Glaticomijs sabriniis northern living squirrel RODENTIA — GeOMVIDAE Tfioinoini/.s t(dpoidcs northern pocket gopher Tlioinotnijs hottac RODENTlA — CaSTORIDAE botta pocket gopher Castor canadensis beaver RODENTIA — MURIDAE Reithrodontoinij.s megaloti.s western hanest mouse Peronnjsctis maniculatu.s deer mouse Peroiui/sciis hoijUi Clcthrionomys gapperi Ondatra zihetlucns bnish mouse red-backed \'ole muskrat Phenacomtjs intenncdht.s heather \ole Microtiis niontantis montane vole Microtus longicandiis long-tailed \ole Arv'icola ricliard.soni water \ ole RoDENTiA — Zapodidai: Zapu.s princeps Rodentia — Eretuizontida}-: Erethizon dorsatuni western jinnping mouse porcupine '! Carni\ora — Canidae Canis latrans coyote Ca RN I\'0 lU — P ROCYON ID AE Bassarisciis astutiis ring-tailed cat Procyon lotor racoon CaRNI\OR.A — MUSTELIDAE Mtistela frenata long-tailed weasel Mii.stela cnniiwa ermine Mustela vison mink Taxidea taxiis badger Mephitis mephitis striped skunk Carninoiu — Fei.idae Lynx nifiis bobcat Fells concolor mountain lion ARTlODACmLA — CER\aD.\E CeiTus canadensis Ochcoileus hem ion us elk mule deer Alces anwrieanus moose 1992] Red Butte Canyon Research Natural Area 117 Some of the larger species ha\e been observed only occasionally, such as the bobcat, mountain bon, and moose. But others such as the mule deer, elk, and coyote are obsen'ed with high fre(juenc\' at some seasons. A rather rich rodent fauna inhabits the canyon, with many of the species preferentially occupying the moist riparian communities of grasses, forbs, and shrubs. Thus, the red-backed vole, heather vole, montane vole, long-tailed xole, water vole, and jumping mouse are \irtuall\' restricted to the small mesic meadows along Red Butte Creek and its tributaries. Similarlv, the three species of shrews in the canvon are distributed almost exclusively in the riparian habitats. In some larger meadows, such as along Par- leys Fork and at Porcupine Gulch, the microtine rodents are distributed in a strongK' zonal pat- tern. Long-tiiiled voles are found in the driest parts of the meadows, montane \ oles in the more mesic areas where grasses, sedges, and forbs comprise a diverse community, and water voles in the immediate streamside area, their burrows often entering the bank at the waters edge. Red-backed voles and heather voles are t\picalK' found around the bases of willows in the meadows, as well as around the edges of conifers at higher elevations. A few species are found onl) at higher eleva- tions in association with Pseudotsuga menziesii (Douglas-fir) and Popiihis trcmuloides (aspen). These include the red squirrel, Uinta ground squirrel, yellow-bellied marmot, and least chip- munk. The oak-mountain mahogany zone seems to be the preferred habitat of the rock squirrel and perhaps the ring-tailed cat as well. Sexeral dissertations dealing with the ecolotA" and plnsiologiciil adaptations of shrews, microtine rodents, and jumping mice have utilized studv sites in Red Butte Canyon (Forslund 1972, Cranford 1977). A\'iAN Fauna In his studv of the birds of Red Butte Canyon, Perr\- (1973) found that 106 species occurred in the area during his studv. Of these, 32 species are penuanent residents and 44 are summer residents. The remainder (30) are migrants or winter residents. The permanent resident birds include: F.\LCONIFOKMES — ACCIPITRIDAE Accipiter gentilis Goshawk Accipiter striatus Sharp-shmned Ha\\k Accipiter cooperi Cooper's Hawk Gai.i.ifohmks — Tithaonidaf: Dciulragapus ohscu nts Boiuisd mnhclltis GaLLIFOKMKS — PllASIAMDAK Lopliortijx califoniiciis Ph as ian u .s colcli i ctis Alcctoris graced Stricifokmks — Stri(;idae Otiisflatniiwoltis Btiho virginianiis Asia otus Coa\CIIFORMES — Au.edinidaf. Mcgaccnjlc ah yon PiCIFOKMES — PiClDAE Colaptes cafer Sphyrapicus varius Dcndrocoptis villosus Denclrncopus puhescens PaSSERIFORMES — COR\ID\E Cyanocitta stclleri Apheloconui coenilescens Pica pica PaSSERIFORMES — PaRIDAE Pants atricapilliis Panis aanJ)eli Psa It rip a nis m i niu ms PASSERIFORMES — SlTTIDAE Sitta canadensis PaSSERIFORMES — CeRTIIIIDAE Ccrthia familiark PaSSERIFORMES — CiNCLIDAE Cinclus mexicanus PaSSERIFORMES — TURDIDAE Myadestes townsendi PaSSERIFORMES — SYL\IID.\E Regiihis satrapa PaSSERIFORMES — STURMDAE Sturnns vulgaris PASSERIFORME.S — ICTEHIDAE Stiimella neglecta Passeriforme,s — Fhincillidae Ca qwdaciis mexica nus Spinas pinus jiinco orcganns Blue Grouse Ruffed Carouse C'aliforuia ^uail Riug-neeked Pheasaut Chukar Flammulateil Owl Great Homed Owl Long-eared Owl Belted Kingfisher Red-shafter Flicker Yellow-bellied Sapsucker Hair\' Woodpecker Downv Woodpecker Steller's Ja\ Scnib JaN' Magpie Black-capped Chickadee Mountain Chickadee Common Bushtit Red-breasted Nuthatch Brown Creeper Dipper Towiisend's Solitaire Golden-crowned Kinglet Stiirling Western Meadowlark House Finch Pine Siskin Oregon Junc(j In addition to the species that are permanent residents in Red Butte Canvon, the following list of summer residents represents .species thiit probably also nest in the camon: Anseriformes — Anatidae Anas platyrhtpiclios Falconiformes — .'\(x:ii'itridak Biiteo jainaiccnsis Acjuila chn/saetos F AI ,C:ON IF( )R M ES — FaLC:ON I DAE Falco sj)arcerius ClIARADHIIFOR.MES — ScOU)I'ACIDAJ-: Aciitis nuictdaria Spotted Sandpiper COLUMBIKOHMES — COLL.MHIDAK Zi'naidnra macraura Apodiformes — Tr(k:iiii.idae A rch ill )clt us alcxandri .Mallard Duck Red-tailed Hawk (Golden Eagle Sparrow I lawk Mourning Do\e Sclasf)lu>nis platyccrcus P.VSSERIFOHMES — TlR^NNIDAE Empidonax ohcrholseri Black-chinned Hummingbird Broad-tailed Hummingbird Dusk-x Flycatcher 118 Great Basin Naturalist [Volume 52 Empidonax diffirilis Western Flyeatclier Coittopiis surdidulus Western Wood Peewee PaSSEHIKORMES — HiKUNDIMDAK Tacliijcincia tluilassina N'iolet-green Swallow Iridoprocnc hicolor Tiet> Swallow Rifxiiia riparia Bank Sw;i!low Stel^idof)tcn/x nificollh- Rough-\\ino;ecl Swallow Iliniiidc nisticti Bam Swallow PeiroclichdoH piirrlumotii (."lift Swallow Passf.hifohmfs — TK(x;i.t)i)rrii)AK Tn)'assin's Finch Spiniis tristis American Croldtinch Cdilonira cldoruni (ireen-tailed Towhee Pipilo crytlirotlxihiuis Rufous-sided Towhee Pooecetes '^rainiiifiis Vesper Sparrow Jtinco caniccps (irav-headed Jmico Spizella pdsserina (Shipping Sparrow Melospiza inelodia ^"'igi Sparrow Role of Research Natural Areas Research Natural Areas proxide several spe- cific acKautages to the natiou's scientific comniunit)', which are tvpically not othenvise available. These include potential use of an area that has had minimal human interference and has a reascjnable assurance of long-term exis- tence, and the potential association and interac- tion of scientists from different disciplines leading to discoveries unlikely to occur without such an association. Conducting research at common locations is kev to developing these interactions. Research Natural Areas not onlv assist in the progress of basic science, but also provide federal and state agencies with informa- tion upon which to base management decisions. The melding of ecosvstem presenation and research on basic ecological processes at Research Natural Areas provides numerous valuable options to societv. The Red Butte C'anvon RNA serves this puipose well. Although initially affected bv human activities during the early settlement of the Salt Lake Valley, the canyon was soon set aside bv the federal govern- ment and has now had nearlv a centuiy to recover (tliough the loss of beaver represents a significant impact to the ecologv of the riparian ecosystem). Other canyons in the \Vasatch Range have not received equivalent protection. As we move into the twenty-first centuiy, there will he increasing pressure to understand the dynamics of ecological systems and man s impact on ecological processes. Maintained as a protected watershed, the Red Butte Canyon RNA provides a unique oppoitunitv' for addressing these important issues to human societ)' and to the presenation of our environ- ment. Unprotected, it is an invaluable resource lost forever. Federal laud-management agencies have been developing a national system of Research Natural Areas since 1927. More than 4{)() areas have received this designation nationally. Since inception of the RNA Program, there have becMi two priman puqx).ses for Research Natural Areas: 1. to presene a representative arrav of all significant natural ecosystems and thtii- inherent processes as baseline areas; and 2. to obtain, through scientific echication and research, information about natural svstem components, inherent processes, and com- parisons with representative manipulated svstems. Literature Cited An asterisk (°) refers to studies conducted in Red Butte Canvon, but not .specif icallv cited in this manuscript. Al.HKK B. ].. L. M. Sm 1,1/ and S. Coodkk ii 19SS. Atlas ol die \ascularplantsol Utah. Utah Museum of Natural I iiston. Salt Lake Cit\. 670 pp. A\<)\V\l()l s 1954. HistoiT of Fort Douglas. (Compiled In I'"oi"t Douglas Arm\ Engineers Office. Ar\o\\ U a. 1971. NascularlloraofRed Butte (:an\ on. Salt LakeO'onnty, Utah. .Masters thesis, Uni\crsit\ of Utah, Salt Lake Citv'. 3-. . 1979. Nutrient concentration patterns in a stream draining a montane eco.swstem in Utah. Ecolog\ 60: 1184-1196. °Bhk\\STF.H. W. 1951. (;all wasps pnHliicing falls on the scrub oak, (^iwrcus gfiinbdU Nutt. Unpublishetl masti'r's thesis, Universit)' of Utah, Salt Lake Citv. C.M.nwKi.i. M. M. 1985. Cold desert. Pages 198-212 //( B. F. ("habot and II. A. Moonev, eds.. Physiological ecolog\' of North American plant commnnities. (Chap- man unci Hall. London. Co.MSTocK, J. P., and J. R. Ehlekin(;kh 1992. Plant adap- tation in the Creat Basin and Colorado Plateau. Great Basin Naturalist. In press. ( ;<)TTAM. W. P., and F. Ev.ws. 1945. A comparati\ e stnd\ of grazed and ungrazed canyons of the Wasatch Range, UtiJi. Ecologx 26: 171-181. Cii WFOHi), J. A. 1977. The ecolog\ of the western jumping mouse. Unpublished doctoral dissertation. Uni\ersits' of Utah, Salt Lake Cit)'. °Ch()FT, A. R., L.WooDWAHU. and D. A. Andfhson 1943. Measurements ol accelerated erosion on range-water- shed laud. Jonniiil of Forestn" 41: 112-116. CJlU)N(^)i;isT, A. |. 1947. Re\ision of the North American species of £n^('r(»;i. north olMcxico. Brittonia6: 121- 302. . 1981. /\n integrated .swstem of classification ol How - ering plants. Columbia Uui\ersit\- Press. New York. 1262 pp. DaihI'AMIKF. R. F. 1943. Wgetational zonation in the Rock-)- Mountains. Botanical Review 9: 325^393. D.\\\s()\. T E., and j. R. Eiii.FHlNCFH 1991. Streamside trees that do not nsi' stream water Nature 350: 335- 337. . 1992. (Jender-specific plnsiologv, carbon isotope discrimination, aTid habitat distribution in boxelder. Acer ncgitndo. Ecolog\-. In press. Dkia'cia, E. IL.andW. H.'S(:iilfsin(;fh 1990. Ecophxs- iok)g\ of C^reat Basin iuid Sierra Nevada xegetat ion on contrasting soils. Pages 143-178 /h C. B. Osmond. L. F. Pitclka, and C. M. Hidy, eds.. Plant biolog\- of the Basin and Range. Springer \erlag, New York. Di\A, S. J. 1970. An evaluation of ph\siological response to water stress as a factor influencing the distribution of six woocK species in Red Butte (]an\'on, Utah. Unpub- lished doctoral dissertation. Uuixersitx' of Utah, Salt LakeCit\. DiNA S. J., and L. C. Ki.ikoff. 1973. Carbon dioxide exchange by se\eral stream side luul scnib o;ik coiuniu- nit\ species of Red Butte Can\on. Utah. Americiui Midland Naturalist 89: 70-80. DoHKowoi.sKi. J. P., M. M. Callow Ft. 1, and J. 11. Ricii- AHDS. 1990. Basin h\droIog\' and plant root systems. Pages 243-292 in C. B. Osmond, L. F Pitclka, and C. M. Hidy, eds.. Plant biologxof the Basin and Range. S])i-inger V'erlag, New York. D()\()\AN. L. A., and J. R. EllLKHlNCEH 1991. I'k-ophysio- logical differences among pre-reproductive and repro- ductive classes of sexeral woodx species. Oecologia 86: 594-597. Elll.FKlNCFH. J. R. 1988. Changes in leaf characteri.stics of species along elevational gradients in the Wasatch Front, Utah. American journal of Botany 75: 680-689. E\A\s, F. R. 1936. .A comparati\e study of the vegetation of a grazed and imgrazed cau\-on of the Wasatch Range. Unpublished master's thesis, Unixersitv of Utah, Salt Lake City FoHSLL \i) L. (;. 1972. Endocrine adjustments in .A//cT()/».9 iHDiiidniis populations from laboraton- anil natural en\ironments. Unpublished doctoral dissertation, Tulane Unixersih', New Orleans. Louisiana. Fhffmax D. C, K. t Il\Hi'i;i^ and W. K. OsiLFit 1980. Ecologs ol plant dioeev in the intenuonntain region of western North America and ("alilornia. Oecologia 44: 410-417. Fiu:fman D. C. L. G. Ki.ikoff. and K. T. Hahpfk 1976. Differential resource utilization b\- the sexes ol di(X'- cious plants. Science 193: 597-599. Hfix a. G., R. W. Mowfr. and C. A. IL\hh 1971. Water resources of Salt L;ikc Counh', Utah. Utah Department of Natural Resources Technical Publication 31. HiiiiiAHD. C. G. I98(). Fort Douglas, 1862-1916. Unpub- lished doctoral dis.sertation, Universitx' of Utali, Salt Lake Cit\-. iloucnrrox. |. (;. 1969. C^haracteristics of rainfall in the Cireat Basin. Desert Research Institute, Uui\ersit\ of Ne\ada, Reno. 205 pp. °Jami;s F K., ]\\. 1950. The ants of Red Butte Canxon. Unpublished masters thesis. Uni\-ersit\' of Utah, Salt Lake City. Ki.FlNFH E. F. 1967. .\ slud\ of the vegetational couuMuiii- ties of Wvd Butte Can\on. Salt Lake Countv-, Utali. Unpublished masters thesis, Uni\ersit\- of Utah, Salt I -ake City. 53 pp. Kffinfk, E. F, and K. T. IIahi'FU 1966. \n investigation ( >f as.sociatiou patterns of prexaleut grassland sjxx'ies in Red Butte Canyon. Salt Lake Countx, Utdi. Ut;ili Academy of Science, Arts, and Letters 43; 29-36. °L\FFFinv. K. M. 1949. A preliminan'. study of the spiders of \\<.'(.\ Butte Can\on. Unpublished master's thesis, UTiixt'rsity of Utah,' Salt Lake Cih. Lii I INCFH. D. B. 1985. Fenis and fern allies. Smithsoniiui Institution Press, Washington, D.C. 389 pp. .\Iahsfi.i.. R. E.,and R. L. Tiihfft. 1960. Geologic map of Salt Lake Countx. Utah. Utah Geological iuid Mineral- ogical Su.AiA Reprint Series, R.S. 83. Scale 1:62,5(X). .\lvriii\s .\1. E., and L. Constance. 1944-45. Umbellifeiae. North American Flora 28 B: 43-297. "Nfcis N. C, P J. Behceh. and L. G. F'orslund. 1977. Repr<)(lucti\-e strategy oi Microtiis montanus. Journal of .Vlannu;ilog\' 58: ,'347-353. Pi:iun. .M. L. 1973. Species composition and densit\- ol the 120 Great Basin Naturalist [Volume 52 birds of Red Butte (Canyon. Unpublished masters tliesis, University of" Utah, Salt L;ike City. "Peterson, B. V. 1953. TiLxonomy and biology of the black flies of Salt Lake County. Unpublished master's thesis. University of Utali, Salt Lake City. S.AMUELSON, J. A. 1950. A (juantitative comparison of die algal populations in tu'o Wasatch Mountain streams. Unpublished masters thesis. University of Utah, Salt Lake City. ScilEFFEK, V. B. 1938. Management studies of transplanted beaver in the Pacific Northwest. North American Wild- life Triinsactions 6: 320-326. SlEREN, D. J. 1981. The taxonomy of the genus Ettthaiiiia. Rhodora 83: 557-579. Smedlev. M. p., T E. Dawson. J. P. Comstock, L. A. Donovan. D. E. Sherrill. C. S. Cook, and J. R. Ehlerinc;er 1991. Seasonal carbon isotopic discrim- ination in a gr;issland community. Oecologia 85: 314- 320. Smith, S. D., and R. S. Nowak 1990. Ecophvsiology of plants in the intermountain lowlands. Pages 179-241 in C. B. Osmond, L. F. Pitelka, and G. M. Hidy, eds.. Plant biology of the Basin and Range. Springer Verlag, New York. Smith, W. K.,and A. K. KnapP. 1990. Ecophysiologyofhigh elevation forests. Pages 87-142 in C. B. Osmond, L. F. Pitelka, and G. M. Hidy, eds., Plantbiology of the Basin and Range. Springer Verlag, New York. Stoddart, L. a. 1941. The Palouse grassland association in northern Ut;Ji. Ecology' 22: 158-163. Swanson, G., E. Ki,einer, and K. T Harper 1966. A yegetational study of Red Butte Canyon, Salt Lake County, Utah. Proceedings of the Utah Academy of Science, Arts, and Letters 43: 159-160. "Treshow, M., and K. T Harper 1974. Longexity of perennial forbs and grasses. Oikos 25: 93-96. Treshovv, M., and D. Stewart 1973. Ozone sensitivity of plants in natural communities. Environment^ Conser- vation 5: 209-214. Tryon, R. M., iuid A. F. Trvon 1982. Ferns and allied plants. Springer- Verlag, New York. 857 pp. Van Horn, R., iind M. D. Crittenden, Jr. 1987. Map showing suriicial units and bedrock geology of the Fort Dougliis Quadrangle and parts of the Mountain Dell and Salt Ltike City North Quadrangles, Davis, Salt Lake, and Morgan Counties, Utali. U.S. Geological Survey Miscellaneous Investigations Series, Map I- 1762. Scale 1:24,0(X). "ViCKERY, R. K., Jr 1990. Pollination experiments in the Mimulus cardinalis-M. leivisii complex. Great Basin Naturalist 50: 155-159. "Waser, N. M.,R.K.Vi(:keryJh and M.V. Price 1982. Patterns of seed dispersal tuid population differentia- tion in Mimulus gut tat U.S. Evolution 36: 75.3-761. Weber, W A. 1987. Colorado flora: western slope. Ck)lo- rado Associated University Press, Boulder. 530 pp. Weber, W A., and R. Hartman 1979. A North American representative of a Eurasian genus. Phvtologia 44: 313- 314. Welsh, S. L., N. D, Atwood L. C. Hiocins and S. Goodrich 1987. A Utali flora. Brigham Young Uni- versity Press, Provo, Utah. 894 pp. Werk, K. S., J. R. Ehlerincer, and P C. Hari.ev 1986. Formation of fiilse stems in Ctprufptenis longipcs: an uplifting example of growth form change. Oecologia 69:466-470. Whitney, H. R. 1951. A comparison of the aquatic iiuerte- brates of Red Butte and Emigration Creeks, Unpub- lished master's thesis. University of Utali, Siilt Lake City. Woodward, L., J. L. Harney, K. M. Donaldson, J. J. Shiozaki. G. W Leishman, and J. H. Broderick. 1974. Soil survey of Salt Lake area, Utah. U.S. Soil Conservation Service in Cooperation with Utah Agri- cultural Experiment Station. 132 pp. Received 14 November 1991 Accepted 1 June 1992 Appendix Nomenclatural Changes in the Flora, 1971-1990 The following is a list of nomenclatural and orthographic changes made since pubUcation of the Vascular Flora of Red Butte Canyon, Salt Lake County, Utiili (Amow 1971). Family names of flowering plants are changed to accord with those used by Cronquist (1981). All other name changes are contained in Welsh et al. (1987) unless otherwise specified. Amaranthace.\e Anuiranthus graecizans of Americiui authors, not L. = A. hlitoides Wats. AMARYLLIDACEAE = LiLIACEAE Brodiaea douglasii Wats. = Triteleia grandiflora Lindl. Anacardiaceae Blius radicans L. = Toxicodendron rijdhergii (Small) Greene Berberidaceae Berheris repens Lindl. = Mahonia repeiis (Lindl.) G. Don Boraginaceae Cnjptantha nana (Eastw.) Pays. = Cnjptantha humilis (Gray) Pays. Hackelia jessicae (McGregor) Brand = H. micrantha (Eastw.) J. L. Gently Lappula echinata Gilib. = L. squarrosa (Retz.) Duniort. (Weber 1987) Cactac'eae Opuntia aitrea Baxter, misapplied to O. macrorhiza Engelm, Caryophyix.'^ceae Cerastium vulgatum L. = C.fontanuin Baumg. Stellaria janwsiana Torr. = Pseudostellaiia jamesiana (Torr.) Weber & Hartman (Weber and Hartinan 1979) Cel,\straceae Pachistinui = Paxistima ChEN()POL5IACEAE Sal.sola kali L. = Sal-sola iherica Sennen &; Pau CX)MP0SITAE = ASTEIUCEAE A-iter chilensis Nees = A. ascendens Lindl. Haplopappus n/dhergii Blake = H. watsonii Gray Lactuca pulchella (Pursh) DC. = L. tatarica (L.) C. A. Mey Matricaria matricarioides (Less.) Porter = Chamomilla suaveolens (Pursh) Rydb. Solidago nemoralis Ait. = S. sparsiflora A. Gray S, occidentalis (Nutt.) T. 6c G. = Eutluimia occidentalis Nutt. (Sieren 1981) Taraxacum laevigatum (Willd.) DC. = T. officinale Wiggers (Weber 1987) 1992] Red Butte Canyon Research Natural Area 121 Vit^uicra inultiflora (Nutt.) Blake = HcUomrris tnullifliu-a Niitt. CORNACEAE Comtts stolonifcra Michx. = Coniiis scrirca L. Ckuc:ikkiuk = Bkassicaceae Arahi.s divaiicar-jui A. Nels. = A. Iiolhorllii Homem. Rorippa islandica (Oed.) Borb. = R. palnstris (L.) Besser R. tninaita (Jeps.l Stuckev = R tciicrriitKi (»reene CUSCUTACEAE Cusctita campcstiis Yiinck. = C. pciifdfiona Engelm. Cypehaceae Carex utriculato Boott = C. rastmta Stokes Gramineae = PoACEAE (Amow 1987) Agroprjron caninum (L.) Beaiiv. = Eh/iim.s tiiiclit/caulns (Link) Shinners A. dasijstdcJujum (Hook.) Scribn. = Eh/iims lanceolatus (Scribn. & Sin.) Gould A. ititcniirdiuin (Host) Beaux'. = Eh/uins hi.spiilits (Opiz) Meld. A. siuithii R\dl). = Ehpiius sntithii (R\db.) (iould A. spicatum (Pursh) Scrilin. = Eh/mtis spiciittis (Pursli) Gould Agrostis alba L. = A. stolonifcra L. A. semiverticillata (Forsk.) C. Christ. = Poli/pofioit scmi- verticillatHS (Forsk.) Hylander Arktida loiigi.scta Steud. = A. purpurea Nutt. Bromus hrizacfonnis Fiseh. & Mev- = B. hhzifonnis B. commutatiis Schrad. = B. japonicnsThymh. Gltjceria data (Nash) M. E. Jones = G. striata (Lain.) Hitehc. Hesperochloa kiiigii (Wats.) Rvdb. = Leucopoa kingii (Wats.)W. A. Weber Kiieleria cristata Pers. = K macrantha (Ledeb.) Schiilt. Onjzopsis hijmenoides (R. & S.) Ricker = Stipa lupncnoidcs R. & S. Poa saiidbergii \'ase\- = P. secunda PresI (Amow 1981) Sitanioii juhatum ]. G. Smith, misapplied to Eltpnus ehjinoidcs (Raf.) Swezev Stipa occidi'ittalis Thurb. = S. ueisouii Scribn. JUNCACEAE Junais bait ic US W'iWd. = J. ar(tki/.v Willd. J. traciji R\-db. =/. cnsifolius Wikst. LaHLYPAI-; = L'WIIACKAE Moldavica parviflora (Nutt.) Britt. = Dracocrpluiluin paniflonun Nutt. Lkcuminosae = Faba(;E;VE Mor.\{:eae = Cannabaceae Hnmidus lupulus L. = H. amcricanus Nutt. Ona(;iu(:e.\e EpilohiuDi pauiculatu)n T. & G. = £. braclniraqyuin Presl E. ivatsoiiii Baibev = E. ciliatuin Raf. Oenothera hookeri T & G. = O. data H.B.K. Zaudincria iiaiTcttii A. Nels. = Z. latifolia (Hook.) Greene Orobanchaceae Orobandw califoritica Cham. & Schleclit. = O. conpnbosa ( Rydb. ) Ferris Polemoniaceae Iponiopsis aoarealifoniia, during 1984-87. Deer initiated .spring migration from the v\anter range at about tlie same time in all )ears and made extensive use of holding areas at intermediate ele\ations. Radio-telemetered deer showed strong fidelitv^ to summer riuiges o\er as manv as four years. Fall weather produced different patterns of fall migration. Storms during October produced a pulsed migration, in which most animals migrated to the winter range during or soon after the storm; in a year without a storm, fall migration was gradual. Despite the influence of storms on the pattern of ftdl migration, the median date of fall migration bv females did not var\- over vears; howe\'er, among males it was later in a year without fall storms. Kcij words: mi^ratioiK mule deer. Otlocoileus hemionus, sex differences, icetitlier radio teleinctn/. C'alifoniia. Seasonal migration is common amongawdde variety of vertebrates (Baker 1978), including large terrestrial mammals (McCullough 1985, Fn'xell and Sinclair 1988). Migration ultimately contributes to individual reproductive success (Baker 1978). Proximally, however, migration is related to the seasonal availabilitv' of resources (Sinclair 1983, Garrott et al. 1987). Migration is a common phenomenon among mule deer {Odocoileus lieiniontis) in the mountainous western United States, and various studies have described aspects of nuile deer migration (Rus- sell 1932, Leopold et al. 1951, Gniell and Papez 1963, McCullough 1964, Bertram and Rempel 1977. Garrott et al. 1987, Loft et al. 1989). Ilowexer, questions remain as to the influence of proximate factors, especially weather, on the timing of migration. In addition, because .stud- ies of mule deer involving radio-telemetn' rarely have inchuk'd males (e.g., Garrott et al. 1987, Loft et al. 1989), little is known of differences between the sexes in migration patterns. My objectives were (J) to describe the timing and pattern of seasonal migration of mule deer in the ea.stern Sierra Nevada, C'alifor- nia; (2) to test the hvpotheses that there were no differences b)- sex or year in the timing and pattern of luigration and degree of summer- range site fidelity-; and (3) to relate ob.sc'ncd migration patterns to other aspects of tlie (X'ol- ogy- of these animals. Study Are.\ The Sierra Nevada is a massive granite block tilted toward the west, extending for 600 km in a generally northwest-southeast direction (Storer and Usinger 1968). The west side of the moun- tain range slopes gradually for 75-100 km, from the foothills near sea level to the crest at 3000- 4500 m. The eastern Sierra Nevada is more narrow and steep than the west side, with fre- quent elevational changes of 3000 m in <10km. A population of 3000-6000 Rocky Mountmn mule deer (Odocoileus Ji. Jieniioiuis) wanters at the base of the eastern escaipment of the Sierra Nevada in Round Willev. Invo and Mono coun- ties, California, about 15 km west of the town of Bishop (Fig. 1). An area of about 90 knr of Roinid \^alley is used bv' mule deer as winter range, at elevations from about 1450 to 2100 m. Pine Creek forms the dividing line between what is termed the Shetwin Grade (SG) deer herd to the north and the Buttermilk (BM) herd to tht" south. These deer are hunted under bucks-onlv regulations, and posthunt adult sex ratios of 7-12 males: 100 females occm"red dvning this studv" (California Department of Fish and (rame. Bishop, California). As winter storms h'oni the Pacific Ocean rise up the western slope of the Sierra Nevada, thev ck^posit rnoistiu'e, leaving a mucli more arid riiin sliadow on the t>ast side. Precipitation in the nepartincnt oC For.sin .nul Kcsourcc VIaiiui;i-iii.-nt. .iiul Vli )t\rrt,-l)r.i(.-'/.(K)l(>i,r\. Iniu-rsilN 37 C. Jannarv is the coldest month, with tion 1987). Precipitation is strongly seasonal an a\erage temperature of 4 C and frequent 124 Great Basin Naturalist [Volume 52 nighttime lows of <-15 C. Potential evapo- transpiration is 66.8 cm, or more than four times the mean precipitation. Vegetation on the winter range is t\|:)ical of the Great Basin Desert and conforms to the sagebrush belt of Storer and Usinger (1968). Shnibs are dominant, and blackbmsh (Coleoayne ramosissiina), rabbitbnish (Clin/sotJunnnus spp.), big sagebnish {Artemisia trident at a), and antelope bitterbrush (Purshia trident at a) are most common. Deer summer ranges are on both sides of the Sierra crest, at elevations from about 2200 to >3600 m (Kucera 1988), and include the sagebrush, Jeffrey pine {Piniis jeffretji). lodgepole pine {P. murraijana)-red fir {Abies ma^nifica) , subalpine, and alpine belts (Storer and Usinger 1968). Livestock use of deer winter range was light, consisting of 129 animal-unit-months of use by cattle, restricted to part of the SG range from 1 April to 15 October (U.S. Department of the Interior 1990). Use of deer summer areas by livestock (including horses, cattle, and sheep) varied from ver\' heavy in more accessible loca- tions on the east side of the mountain range to none at higher elevations and more remote areas. Methods Fieldwork was conducted from Januar)' 1984 through Mav 1987. Deer were captured on the winter range Januar)' through March 1984 and January and February 1985 with a variet\' of methods including Clover traps (Clover 1956) baited with alfalfa, drive nets using a helicopter, and remotelv triggered drop-nets; net guns fired from a helicopter and tranquilizer darts also were used to capture selected males. Deer cap- tured in 1984 in Clover traps were chemicalK immobilized with Rompon (xylazine hvdrochlo- ride), the effects of which were reversed with yohimbine after handling (Jessup et al. 1985). Deer were captured also during May 1984 and 1985 witli tran(|uilizer darts on a spring migra- tion "holding area ' (Bertram and Rempel 1977) about 50 km north of the winter range. This is an area where deer congregate for 2-6 weeks before continuing to areas occupied during the summer. I fitted 8 males and 9 females from the BM winter range, 7 males and 10 females from the SG winter range, and 10 females captured on the spring holding area with radio collars (Telonics Inc., Mesa, Arizona). All deer were <2.5 years of age. I attempted to distribute cap- ture efforts throughout accessible areas to min- imize biases in the marked sample. I selected females for telemetry to include all age classes of adults; however, I selected males to receive radio collars on the basis of large size and rela- tivel)' old age. I excluded smaller, younger males because of concerns arising from body growth; males do not approach maximal neck circumfer- ence until about 4 years of age (Anderson 1981), and this, combined with seasonal neck swelling during rut, could result in injury caused by radio-telemetry collars. Older males have achieved nearly maximum body growth; I allowed for seasonal neck swelling bv attaching the nonexpandable collars with a circumference 20-25% larger than the animal's neck circum- ference after rut, measured midway between head and shoulders. I noticed no serious prob- lems resulting from the use of radio collars on male deer in this study, although after a )ear or two, some fur appeared to be rubbed off the backs of the necks; a similar situation occurred with telemetered females. Collars on the males moved toward the head when the necks swelled during rut and hung loosely at other times. While animals were on the winter range, I determined at least once per week, and usually more often, whether each radio-marked animal was on the BM or SG winter range bv observing the direction of transmitter signals received from standard locations. These data were sup- plemented bv additional radio locations and visual locations as observers moved through the winter ranges. During spring and fall migra- tions, and during summer, locations of teleme- tered deer were determined from a fixed-wing aircraft, from a vehicle, and from the ground. During the spring, locations were determined several times per week until the aniniiils crossed the crest of the Sierra. Due to the remoteness of most summer ranges in roadless wilderness areas, frequency of locations of animals, deter- mined from the air and the ground, on the west side of the Sierra Nevada was approximately twice per month. Of 42 deer that reached summer ranges, I located 38 from the ground. Twenty-two deer were followed for more than one sunmier. Of these, 10 (45%; 1 male, 9 females) were located in two consecutive sum- mers, 9 (41%; 3 males, 6 females) in three con- secutive summers, and 3 (14%; 1 male, 2 females) in four consecutive summers. For 1992] Migration of Mule Deer 125 these animals I expressed ficlelih' to summer range as the greatest linear map distance between mean locations in consecutive sinii- mers (1 July-7 September). During the fall, locations of animals were monitored from the east side of the Sierra crest at least several times per week, and frequently daily. I could thus determine, within several davs and often within one dav, when telemetered deer from the west side of the crest crossed to the east side. I dixided annual migration into three peri- ods: ( 1 ) leaving winter range, defined as ascend- ing to an elexation >2100 ni; (2) crossing the Sierra Nevada crest in spring; and (3) crossing the crest in fall. The last two applv only to those animals (n - 34) that summered west of the crest. Because of logistic difficulties in locating animals on the west side of the crest, I did not attempt to determine precisely when animals crossing the crest reached their summer ranges. The steep eastern slope of the Sierra Nevada provided the opportunity to determine the pres- ence or absence of a radio-marked animal on the east side with little error. In situations in which I could not deteninine an exact date of crossing, I estimated the date as the midpoint of the interval in which I did and did not receive a signal. For analysis I determined frequencies of movement by week during an 8-week period of leaving the winter range beginning 1 April, a 7-week period of crossing the crest in spring beginning 15 May, and an 11-week period of crossing the crest in fall beginning 1 1 Septem- ber. I used the Kolmogorov-Smimov test with chi-square approximation (Siegel 1956) to test for sex differences in the timing of these com- ponents of migration. Steep mountains on the west side of Round Valley constrained move- ment off the winter range to northerlv or south- erly routes; I tested for sex differences in the direction (north or south) of migration from the winter range with the binomial test (Zar 1984:591 ). I expressed temponil patterns of fall migration as the percentage of radio-marked deer in an annual sample crossing the crest during any week. I tested for differences among years in the largest weekly percentage crossing the crest in any year with the Z-test (Zar 1984:396). From April through June of 1985, 1986, and 1987, commencing as soon iis snow conditions permitted, deer were counted from a vehicle along a standardized route of 1 1 km that passed through a major spring holding ari'a located 1-8 km south of the town of Mammoth Lakes, approximately 50 km north of the winter range. These weekly surveys began 30 minutes before sunrise, and direction of travel was alternated on consecutive survevs. Daily precipitation in the fall was measured at the U.S. Forest Service (USFS) weather sta- tion at the Mammoth Lakes Ranger Station, Inyo National Forest, Mammoth Lakes, Califor- nia, at an elevation of about 2400 m. Winter snowfall totals were from the USFS weather station on Mammoth Mountain, at about 2940 m. Results Spring Migration From 1984 to 1986 the first radio-marked deer left the winter range during the first or second week of April in anv vear; in the same years the last radio-marked deer left during the second, third, and fourth weeks of May. For femiJes the median departure date from the winter range was during the third, second, and third weeks of April 1984-86, respectivelv'; for males, the median was during the second week of May and second and third weeks of April, respectively. The frequency differences by sex in vveeklv migration approached statistical sig- nificance (X- '= 5.94, df = 2, .05 .10). The median for both sexes in all vears was the first week of June. The temporal uniformit)' over years in leax- ing the spring holding area for simimer ranges occurred despite greatly different snow condi- tions. In the winters of'l983-S4, 1984-85, and 1985-86, the USFS recorded total snowfalls of 671, 767, and 1021 cm, respectively, on Maiu- moth Mountain, geographically close and at an elevation similar to the passes that migrating deer crossed to reach summer ranges on the western slope. Despite these differences in snowfall and consequent snowpack at higher {4evations, no differences in the timing of spring migration were evident. The snowfall of winter 1 986-87 was only 246 cm, or less than one-{|uar- ter of that of the previous year. Although the .sample si/.(> is small, the median week that three radio-marked males and tu^o radio-marked females crossed the crest in the spring of 1987 was the same as the prexdons year, the first week of June. Thus, the amount of snow on the ground did not appear to inlliience the timing of migration o\-er the Sierra crest in the spring. SunmuM" Range ()1 the 32 deer captiuvd on the winter range that reached summer ranges, 28 (87.5%) crossed the Sierra crest and snnunered on the west side. Sununer range locations of these deer, plus thosc^ of deer captured on the spring rangi\ extended from the headwaters of the Middle Fork of the San Joacjuin Ri\-er south throughout the upper San Joaquin Ri\(M- drain- 700 600 ^ 500 a> 0) Ti »*- 400 o k. 300 E 3 200 100 ^ I I I 1 3 Apr 3 May 23 May 1 2 Jun Figf. 2. Nuniher of inuk' dciT fountcd Iroiii a \ L-Iiicle on standardized weekly sin"\evs at dawn through a spring hold- ing area near the town of Mamniotli Lakes, Mono Countv, Cahfoniia, 1985-87. Suivevs begiui in the .spring when snow conditions made the roads passable. age above about 2134 m into the North and Middle forks of the Kings River (Kucera 1988). Two males and 4 females sunnuered on the east side of the Sierra, from Manuuoth Pass on the north to the North Fork of Bishop Creek on the south. Thus, an area nearly 100 x 25 km seived as sunuuer range for deer from the BM and SG herds. Sunuuer Range Fidelits' Distances between smumer ranges of 22 tle(M' located in consecuti\e \ears averaged 0.7 km (range - 0.2-4 km) for both males (/i = 5) and females (n - 17). Onl\ 1 deer, a female, was >1 km from a prexions location in successive summers; she spent her second sununer about 2.5 km from her first, and her third and fourth about 1.5 km farther awax'. Fall Migration In 1984, 1985, and 1986 die first radio- marked deer crossed to the east side dining the first week of (October and second and fourth weeks of September, respectively; all were females. The last crossed during the fourth week of October and second and fointh weeks 19921 Mk;kati()N()f Mule Dker 127 80 60 40 O 0) 20 "D 0) 1984 Deer, n = 15 Precipitation 1985 Deer, n = 26 Precipitation r~[ / \ ; \ / \ / \ I \ I \ / \ ' ^ .^ \ ' ^ \ / \ / -i, — / 20 — Deer, n = 16 — Precipitation 4.0 2.0 0.0 4.0 £ O c o ^-» a "o 0.0 2 Q. 4.0 11 Sep 25 Sep 9 Oct 23 Oct 30 Oct 13 Nov 2.0 0.0 Fig. 3. Percentage of telemetered mule deer per week crossing the crest ot the Sierra Nevada, ln\o and Mono counties, California, and weekly precipitation measured at the town of Mammoth Lakes, Mono Countv, in the fall of 19S4-86. of Noxember; all were males. In 1984 and 1985 the median week of crossing the crest was the same for both sexes, the third and second weeks in October, respecti\elv. In 1986 the median for females was the third week in October, but was tvvo weeks later for males {X' = 18.72, df = 2, P< .001). Length of time during which fall migration occurred also varied among years. In 1984, 11 of 15 (73%) and, in 1985, 14 of 26 (54%) tele- metered deer, including both sexes, crossed the crest in a one-week period. These proportions were not different (Z = 1.2, F > .11). Howevei; in 1986 no more than 4 of 16 (25%) radio- marked deer crossed the Sierra crest in any week. This proportion was smaller than those of the previous two years (Z = 2.45, P < .007), indicating that in 1986 there was no mass move- ment of deer in a short time period. Differences among years both in timing and in pattern of fall migration were related to the presence or absence of major fall storms (Fig. 3). In 1984, 1.8 cm of precipitation in the form of about 20 cm of snow was recorded on 17 October at Mammoth Lakes; no doubt snow at the passes (400-1500 m higher) used b\- migrat- ing deer was much deeper This storm was accompanied by a rapid moxement oi radio- marked deer over the crest and to the winter range within a few davs. Earlier storms, which resulted in virtually no snow at the recording station, did not trigger movement. In 1985, shortK after a storm on 7 October, there was another rapid movement of deer o\er the crest. The remaining deer appeared gradually on the east side of the crest through 13 November, when the last radioed animal, a male, migrated over the crest following a major winter storm. In both 1984 and 1985 1 saw dozens to hundreds of deer migrating simultaneouslv with the tele- metered animals, and man\' tracks and deep trails in the snow were evident. In 1986 there were no major fall storms. Migration was grad- ual and unpunctuated by am rapid, mass mo\e- ments (Fie. 3). In all cases deer returned to the 128 Great Basin Naturalist [Volume 52 winter range (BM or SG) occupied in previous years. Discussion In this study the timing of mule deer migra- tion from the winter range did not differ among years. This occurred despite large differences in animal condition and vegetation growth mea- sured on the winter range (Kucera 1988). One explanation mav be that these deer had well- defined spring holding areas where they could predictably obtain nutritious forage, avciilable even in years of hea\/y snowfall such as 1986, when hundreds of deer were on the holding area when counts began (Fig. 2). Adult males may leave the winter range somewhat later than females, as reported from western Colorado (Wright and Swift 1942). Given the demands of pregnancy, females might be under greater nutritional stress than males, and if better forage conditions exist on spring ranges, females may tend to leave the winter range sooner to take adxantage of them. Garrott et al. (1987) reported that spring migration of female mule deer in northwest Colorado varied between years by as much as one month, and they attributed these differences to the severity of winters and consequent energetic demands on deer. Bertram and Rempel (1977) reported that California mule deer (O. h. californiciis) on the western slope of the Sierra Nevada varied the timing of their spring migration by two weeks, and attributed this to differences in plant phenology both on the winter range and along the migration route. Loft et al. (1989) also reported a similar relationship between initia- tion of spring migration and anioimt of snow and stage of plant growth in the western Sierra Nevada. In my study most telemetered females migrated from the winter range to the north; males showed no significant selection for direction. I contend that this sex difference is a product of local geomoipliolog)' and land man- agement patterns. Animals moving north had access to an extensive area of the west slope of the Sierra Nevada on national forest lands at elevations of 22()0-28()() m. .'\nimals moving south had access to sunmier range in King's ('anyon National Park at higher and steeper, and thus more barren and less vegetated, eleva- tions (Kucera 1988). The presence of more and better summer range to the north expkiins why most deer of both sexes would migrate to the north. However, those animals migrating to the north were in areas open to hunting both on their summer ranges and along the migration routes. That telemetered males showed no apparent selection for migration direction, whereas most females migrated to the north, probably resulted from the higher hunting mor- talit)-' of males summering to the north, and the absence of hunting in the national park. Although as many males as females would be expected to migrate to the north, the higher mortality of adult males moving north could expUiin the apparent pattern of no directional preference. Because older males are dis- proportionately reproductively successful (Kucera 1978, Geist 1981, Glutton-Brock et al. 1982), the national park may act as a refuge for a large proportion of the most reproductively successful males. Deer in this studv made extensive use of holding areas in the spring (Fig. 2), which may be beneficial because of higher elevation, greater precipitation, and absence of winter f^eeding. Vegetation in these holding areas was largely sagebrush scrub (Munz and Keck 1959), a common vegetation type in the eastern Sierra Nevada. These areas are among the last large areas with vegetation suitable for deer present in the spring before the deer cross the Sierra crest. Large aggregations of deer on the holding areas may result from animals simply collecting in these areas for several weeks before ascend- ing over the crest. Bertram and Rempel (1977) and Loft et al. ( 1989) described a similar pattern of use of spring ranges in the western Sierra Nevada and emphasized the importance of these holding areas in providing herbaceous forage. Further, Bertram and Rempel (1977) reported that spring holding areas typically occurred at the base of an abnipt elevation change, which was true in mv studv. Timing of movement off the holding area and over the crest in spring did not differ among vears or between sexes, suggesting that animal condition or vegetation did not greatly affect this stage of migration. The passes had snow in all years of study when deer crossed, but snow depths differed greatly. However, by spring snow was consolidated, enabling deer to walk over the surface. In 1951 Jones (1954) found that BM deer began moving off the winter range about 1 April, and began crossing a nearby pass about 15 May. 1992] MiciuTioNOF Mule Deer 129 This agrees well with the present obsenations made more than three decades later. In the western Sierra Nexada, Rnssell (1932), Leopold et al. (1951), Bertram and Rempel (1977), and Loft et ill. (1989) described spring migration as an "upward drift" of deer, controlled by the receding snowline and spring plant growth. My study showed a different pattern in the eastern Sierra Ne\ada. The upward moxement of deer w as blocked by the abiiipt elevation change of the mountains. On the more gentlv sloping west side, deer can follow spring gradualK' up slope. On the abnipt east side, the need to cross high- elexation passes prevents such a pattern. The strong fidelity to specific summer home ranges shown b\- individual deer in this stucK is characteristic of mule deer (Ashcraft 1961, Gmell and Papez 1963, Robinette 1966, Bertram and Rempel 1977, Garrott et al. 1987, Loft et al. 1989). With few exceptions, both males and females returned to the same summer home ranges, and winter ranges, for as many as four consecutix'e years. The temporal pattern, pulsed or gradual, of the fall migration in the eastern Sierra Nevada is largeK- determined by weather, particularly snowstorms. In both years with simificant snowfall in October, radioed deer moved rapidly and in a pulsed fashion from summer ranges to the winter range (Fig. 3). In a year without significant fall storms, movement was gradutil, and males migrated significant!)' later than females. Previous studies discussed the relation- ship of snow.storms to fall migration (Russell 1932, Dixon 1934, Leopold etal. 1951, Richens 1967, Gilbert et al. 1970), although some cases were based on anecdotal evidence. Bertram and Rempel (1977) stated that deer on the west slope of the Sierra Nevada moved in anticipa- tion of fall storms, but I found no evidence of this. Garrott et al. (1987) speculated that in northwest Colorado deer moved not because of snow, but to maximize the qualitv of their diets prior to winter. Differences in details of deer migration apparent between mv studv and stud- ies in the western Sierra Nevada and in north- west Colorado indicate that deer migration can be influenced b\- local conditions. Females may be constrained in their timing of fall migration by the nutritional and energetic demands of lactation and smaller body size, by the inabilitx of fawns to cope with severe fall conditions, or both. Males do not ha\e the same energetic, nutritional, or parental constraints. Additionall), as consequence of hunting regula- tions, those males that do migrate early are likely to be killed. ACKN OWLEDG M E NTS Financial support was provided bv Invo and Mono counties, the Sacramento Safari ('lub, National Rifle Association, Mzuri Wildlife Foundation, Boone and Crockett Club, and Theodore Roosevelt Memorial Fund of the American Museum of Natural Historw I thank the California Department of Fish and Game and U.S. Bureau of Land Management for their personnel, logistic, and administrative support. T. Blankinship, X. Koontz, D. R. McCullough, T Russi, T. Taylor, R. D. Thomas, and others were instnnnental in various parts of this work. I thank V. C. Bleich, R. T Bowyer, and D. R. McCullough, and particularh- an anonviiious reviewer for their thcnightful reviews of the manuscript. Literature Cited Anderson. A. E. 1981. Morj^hological ;uid plivsical tluuac- teristics. Pages 27-97 in O. C. Wallmo, etl.. Mult- and black-tailed deer of North America. Uni\ersit\ of Nebraska Press, Lincoln. AsncHAFT, G. C, Jr. 1961. Deer movements of the McCloud flats herd. CiJifornia Fish and Game 47: 145-152. Baker. R. R. 1978. The exolutionarv ecok)g\- of animal migration. Holmes tuid Meier Publishers, New York. Bertram. R. G., ;md R. D. Rempel 1977. Migration of the North Kings deer herd, (laliforiiia Fish and (^ame 63: 157-179. ' Clover. M. R. 19.56. Single-gate deer trap. Gaiifornia Fish and Game 42: 199-201. Glutton-Brock. T. II., F. E. Glinnes.s. and S. D. A1.B0N. 1982. Red deer: ecologv' and behavior of two sexes. Universitv of Chicago Press, Chicago. Dixon, J. S. 1934. A .studv of the life history and food habits of mule deer in C';ilifornia. Gaiifornia Fish and C^ame 20: 181-282. FnvxELL, J. M., iuid A. R. E. Sinclair 1988. Gau.ses and consequences of migration In' large herbi\'ores. Trends in Ecologv' and Evolution 3: 237-241. (iAHROTT, R. A., (;. C. White, R. M. Bartmann. L. H. Carpenter. ;uid A. W. Alldreuc:e 1987. Move- ments of female mule deer in northwest Colorado. Journal of VVilcUife Management 51: 6.34-643. Geist. \', 1981. Behaxior: adaptive strategies in mule deer. Pages 157-223 in O. (-. Wallmo, ed.. Mule iuid black- tailed deer of North .\uicrica. University of Nebraska Press, Lincoln. Gilbert. P R, O. G. Wallmo ant! R. B. Gill 1970. Effect of snow depth on mule deer in Middle Park, Colorado. Journal of Wildlife Management .34: 1.5-33. 130 Great Basin Naturalist [Volume 52 Giu'KLi., G. E., luxl N.J. Papez. 1963. Movements of mule deer in northeastern Nevada. Journal of Wildlife Man- agement 27: 414-422. JESSUP, D. A., K. JoNKs. R. MoiiK. and T. Kucera 1985. Yoliimbine antagonism to .xylazine in free-ranging mule deer and bighorn sheep. Journal of the Ameriean Vet- erinary Medical Association 187: 1251-1253. Jones, F. L. 1954. The Inyo-Sierra deer herds. California Department of Fish and Game, Federal Aid Project \V-41-R. Kucera. T E. 1978. Soci;il behavior and breeding system of the desert mule deer Journal of Manun;ilog\' 59: 463-476. . 1988. Ecolog\- and population dynamics of mule deer in the eastern Sierra Nevada, California. Unpub- lished doctoral dissertation. University of California, Berkeley. 207 pp. Leopold. A. S., T Riney. R. McCain, and L. Te\is. Jr 1951. The Jawbone deer herd. California Department of Fish and Game, Game Bulletin Number 4. Loft, E. R., R. C. Bertra.m. and D. L. Bowman 1989. Migration patterns of mule deer in the central Sierra Nevada. California Fish and Game 75: 11-19. McCuLLOUCH, D. R. 1964. Relation.ship of weather to migratory movements of black-tailed deer. Ecolog\' 45: 249-256.' . 1985. Long range movements of large terrestrial mammals. Contributions in Marine Science 27: 444- 465. MUNZ, R A., and D. D. Keck 1959. A California flora. University of California Press, Berkeley. National Oceanic and Atmospheric Administr.\tion. 1987. Local chmatological data, annual summar\' with comparative data. Bishop, California. Nationtil Cli- matic Data Center, Asheville, North Carolina. RiciiENS, V. B. 1967. Characteristics of mule deer herds and their riuige in northeastern Utah. Joiunal of Wildlife Management 31: 551-666. Robin ETTE, W. L. 1966. Mule deer home range and dis- persal in Utah. Journal of Wildlife Management 30: 335-349. Rus.sELL, C. P. 1932. Se;isonal migration of mule deer. EcologictJ Monographs 2: 1-46. SlEC.EL, S. 1956. Nonparametric statistics for the behavioral sciences. International student edition. McGraw-Hill Kogakusha, Ltd., Tokyo, Japtui. Sinclair. A. R. E. 1983. The function of distance move- ments in vertebrates. Pages 240-258 »i I. R. Suingland and P. J. Greenwood, eds.. The ecologv' of animal movement. Chirendon Press, Oxford, England. Storer, T I., ;ind R. L. Usinger 1968. Sierra Nevada natural liistorv. University of California Press, Berke- ley. U.S. Department OF THE Interior. 1990. Bishop resource management plan and environmental impact state- ment. Bureau of Land Mtuiagement, Bakersfield Dis- trict, Bakersfield, California. Vaughn. D. E. 1983. Draft soil inventorv of the Benton- Owens VtJley tirea. U.S. Department of the Interior, Bureau of Land Management, Bakersfield District, Bakersfield, California. Wright. E., and L. W. Swift 1942. Migration census of mule deer in the White Ri\'er region of northwestern Colorado. Journal of Wildlife Management 6: 162-164. Zar, J. H. 1984. Biostatistical antilysis. 2nd ed. Prentice- Hall, Englewood Cliffs, New Jersey. Received 15 November 1991 Accepted 15 April 1992 Great Basin Naturalist 52(2), pp 131-138 DIATOM FLORA OF BEAVER DAM CREEK, WASHINGTON COUNTY, UTAH, USA Kiiitis II. Yt-arsk ■ , Sanmel R. Huslitortli . and Jeffre\' H. Joluuisei Abstract — Tlie diatom flora of Beaver Dam Creek, Washington County, Utah, was studied. The study area is in a warm Mojave Desert en\ironment at an elevation bet\veen 810 and 850 m. A total of 99 taxa were identified from composite samples taken in the fall, winter, spring, and summer seasons. These taxa are all hroadlv distributed and no endemic species were encoimtered. Three new records for the state of Utah were identified: Gomphoiwis cricnse Sk-v. & Maver, S'avicula el sinensis \ar. lata ( M. Perag. ) Patr., and Nitzschia calkla Cnin. The most important taxa throughout the study as determined hv multiplying percent presence by average relative density (Important Species Index) were Cijniljella ajfinis Kiitz., Epithemia sorex Kiitz., Naviaila vcneta Kiitz., Nitzschia palea (Kiitz.) W. Sm., and Nitzschia microcephala Grun. Kcti liords: Beaver Dam Creek, diatoiris, desert streams. The algal flora ot the Intermountaiii West of North America is not well known despite the fact that numerous studies dealing \\ith algal systems of waters in this region have been com- pleted in recent years. These studies have exam- ined streams, fresh water lakes, saline lakes, thermal springs, and terrestrial habitats (Sommerfeld et al. 1975, Stewart and Blinn 1976, Czarnecki and Blinn 1977, 1978, Blinn et al. 1980, Bush and Fisher 1981; for bibliogra- phies see Rushforth and Merkley 1988, Metting 1991). Algal floras of wanii desert systems are espe- cially poorly known. The present study was ini- tiated to provide additional information on the diatom flora of a desert stream located in west- em North America. We examined the diatom communities of Beaver Dam Creek, a tributary of the Virgin River in southwestern Utah. This paper is intended as a baseline floristic and communit\' study of the diatom communities present in this Mojave Desert stream. We had three objectives in this study: (1) to identify all species of diatoms present in Beaver Dam Creek, (2) to document seasonal variation in the diatom communities of this stream, and (3) to compare diatom populations according to habitat t\pe. Our stud\- reports all diatom taxa present in this stream across four seasons of 1987-88. We studied populations in (1) riffle areas with erosional flow velocities, (2) deposi- tional areas with slower flows, and (3) epipln tic habitats on the stems and leaves of aquatic xas- cular plant vegetation. Site Description Beaver Dam Creek at L\tle Ranch Preserve is located 37°10' North latitude and 114° West longitude in Washington Countv, Utah (Fig. 1). The stream occurs in our study area at an eleva- tion of about 850 m at L\i:le Ranch dropping to 810 m at Tenys Ranch. Our study sites are located along the wash near the ranch house at Lvtle Ranch Preserve and near a smaller out- building at Tenys Ranch. Beaver Dam Creek is a vigorous, braided perennial desert stream. It is important to the entire biota of the area since it is the main source of perenniiil water. The stream through the study area has formed a broad gravel flood plain due to frequent flooding. The stream occurs in bajada and alluxial fan materials derived from the Bull N'alley, Pine Vallev; and Santa Clara mountains (Welsh et al. 1987). Beaver Dam Oeek is fed by seeps, springs, and snowmelt primarily from the Pine Valley Mountains. This area is also characterized by flash floods caused by sevx^re periodic thunder- storms in the summer and fall seasons. For instance, prior to the April 1988 collection, Beaver Dam Wash received 11 days of rtiin J Department of Botany and Range Science, Bngliam Yonng lJnJ\ersit\ . Provo. Ltali 84602. Departmentof Biology, John Carroll University, Universits Heiglils, bliio4411S. 131 132 Great Basin Naturalist [Volume 52 Fig. 1. Map of Beaver Dam VVasli .sliowing tlie location of colletting lotalitit-s at Tern s Raiuli and Lxtle Ranch Preserve. Due to the meandering and clianging nature of Beaver Dam Creek, the stream itself is not sliown on this map. 1992] Diatoms of Bkankh Dam Chkkk 133 producing moderate to severe flooding along the stream channel. This scoured the stream channel, remoxing large amounts of ac^natic \e2etati0n and causing; channel relocation in some areas. The gravel bar in Beaver Dam Creek is gen- erallv higher in the center than at the margins, causing the stream to meander over a wide area \\1th frequent changes of channel during flood- ing (Welsh et al. 1987). The fall in elevation downstream is not constant. Gravel tends to pile up in steps that vary' in length and height. This uneven granular substrate causes the stream to meander along the gravel bar and eventually to sink underground approximatel) four miles below the southernmost collection site (Welsh et al. 1987). The perennial stream reappears infrequenth' as seeps and springs lower in Beaver Dam Wash until merging with the Virgin Rixer. Climate in the stud\' area varies consider- ably, not only diunially and seasonally, but over longer periods of time. Winters are generally cool and drv; summers hot and dry. MiLximum summertime temperatures have been recorded at 45.6 C. Rainfall averages less than 15 cm a year, although this is \ariable due to intense storms (Welsh et al. 1987). The biota of our study area is exceptionally diverse. Mammals, birds, reptiles, amphibians, invertebrates, and a great variety of plants occur in Beaver Dam Wash (Welsh et al. 1987). The stream supports a diverse riparian habitat con- sisting of Fremont cottonwood (Populus freinontii Wats.), Arizona ash (Fraxitms vehitina Torr.), black willow (Salix oooddingii Ball), seep wiWow {Baccharis emorxji Gray//; Torn), numer- ous torbes, grasses, and grasslike species (Welsh et al. 1987). Silty terraces occur immediately adjacent to the wash and have been historically used for cultivation. These areas are dominated by catclaw acacia {Acacia greggii Gray), panicu- late rabbitbrush {Chn/sotJiamnus panicidatus [Gray] Greene), Ambrosia species, and numer- ous others (Welsh et al. 1987). Adjacent uplands support Joshua tree forests {Yucca hreiifolia Engelm.), creosote bush {Larrea tridentata [DC] Gov.), prickly pear cactus {Opuntia en^ehnannii Engelm.), cholla cactus {Opuntia hasilaris Engelm. and Bigel.), and numerous other xerophvtic species (Welsh et al. 1987). Methods Water chemistn,' was sampled at the collec- tion sites for Febmarv, April, and July 1988 using a portable Hach field water chemistry lab. Air temperature and water temperature, dis- solved oxygen, hardness, alkalinit\, and pH were measured. Diatom collections were taken on 21 November 1987, 20 February 1988, 30 April 1988, and 6 July 1988 to docvmient seasonal \ariations in diatom populations. (Composite samples were collected from three habitat t)pes. First, riffle areas with erosional flow rates were sampled by scraping algae from large stones in the creek bed. Second, slow water areas in the stream were sampled by obtiuning sediments, rock scrapings, and visible attached algae. Finally, submerged sedge stems and leaves were scraped or collected at selected localities to studv epiph\'tic assemblages. Due to seasonal changes, it was not always possible to sample all three substrate t\pes at both locations. A total of 19 samples were ana- ly7:ed during the course of the study. Samples were stored at air temperature and retimied to the laboratoiy at Brigham Young University- for analysis. Diatoms were cleared by boiling in nitric acid and potassium dichromate (St. Clair and Rushforth 1977). After rinsing, cleared fnistules were suspended in distilled water and allowed to air dry on cover slips. Strewn mounts were prepared using Naphrax high-resolution resin. Representative slides were examined with Zeiss RA microscopes equipped with Nomarski optics and bright field illumination. An Olym- pus AD photomicrographic system was used to record each taxon. Strewn mounts ha\e been placed in the collections at Brigham Young Uni- versity. A minimum of 500 valves was counted for each sample, and a percent relati\ e densit\- was calculated for each taxon (Kaczmarska and Rushforth 1983). An Important Species Index (ISI) for tcLxa present was calculated by multi- plving the percent frequency of occurrence of a taxon in the samples 1)\- its oxerall average per- cent relative densitv in all samples (Ross and Rushforth 1980, Kaczmarska and Rushforth 1983). This method is useful since it considers both abundance and seasonal distribution of a taxon (Warner and Haqoer 1972). Species diver- sity for each sample was calculated using the 134 Great Basin Naturalist [Volume 52 T./VBU. 1. Mean values for air teinperatiue iuid water chemical paranieter.s taken from collecting loc;ilities in Beaver Dam Creek, Washington Countv', Utah. February April Ji ily L\tle Terry's Lvtle Terrv's Lytle Terry's Air temp. (C) 16.3 17.3 20.5 20.5 33.0 26.0 Water temp. (C) 14.5 17.5 16.8 16.8 24.3 22.3 Di.ssolved O2 (mg/1) 9.5 10.0 9.0 9.0 ( . 1 7.0 Hardness (mg/1) 247.3 276.1 707.5 707.5 281.9 362.4 Alkalinitv (mg/1 195.6 207.1 201.3 224.3 pH 7.3 7.1 6.9 7.0 8.1 7.7 T.\BLE 2. T;t\a present in samples collected from Beaver Dam Creek, 1987-88, Listed with Important Species Index (ISI) values. When ISI is below 0.01, the species is listed ;is a trace (T). Taxon ISI Lvtle Terry Achnanthes affinis Gnin. Achnanthes exi^tia Cnm. Achnanthes hnceolata (Breb.) Gmn. Achnanthes miniitissima Kiitz. Amphora libt/ca Ehr. Amphora pedictihis (Kiitz. ) Gmn. Amphora veneta Kiitz. Cah>nei.s bacilhim (Cnm.) Cl. Cah)neis siliciiht (Ehr.) Cleve Cocconeis pedicuhis Ehr. Cocconeis placentula viu". eti^hjpta (Ehr.) Cleve Cocconeis placentula v;xr. lincata (Ehr.) VH. Cyclosteplianos invisitattis (H. & H.) Ther., Stoerm. & Hak. Cyclotella nu'nc<^hiniana Kiitz. Ci/mbella affinis Kiitz. Cifiuhclla niexicana (Ehr.) Cl. Ct/inhella microccphala Gmn. Ci/nihclla silcsiaca Bleisch Ci/nihclla tiimida (Breb. ex Kiitz.) V.H. Dcnticula dedans Grun. Denticnia clchioxys (Ehr.) Grun. Melosira variam Ag. Meridion ciradare (CJrev.) Ag. Navicida abiskoetisls Hust. Navictda atomus var. permitis (Hust.) L.-Bert. Navinila baeilhnn Ehr. 1.92 1.8 2.6 0.03 0.1 0.1 2.51 3.8 1.1 1.92 3.4 1.3 0.10 0.4 0.1 1.76 2.5 1.1 0.13 0.6 0.1 T T 0.04 0.1 0.1 1.07 3.1 0.8 1.22 1.4 1.1 T 0.72 1.0 0.5 17.57 23.4 13.2 T 0.58 1.2 a.5 0.16 0.4 0.1 T 1.44 2.5 0.4 T V 0.84 1.7 0.5 0.11 0.5 0.1 0.07 0.1 0.3 1.3.25 1.8 35.9 T 0.21 0.5 0.2 0.50 0.5 0.8 0.14 0.2 0.3 2.21 1.1 3.0 0.02 0.1 0.1 0.27 0.7 0.2 T 0.51 0.8 0.4 0.06 0.2 0.2 0.08 0.3 0.2 1.89 2.1 0.2 1.32 1.6 1.5 T T T 0.06 0.3 0.1 T T 0.08 0.2 0.1 0.09 0.2 0.2 1992] Diatoms of Bea\'Er Dam Creek 135 Tablk 2. Coutiiiut'il. Navicula capitatoradiata Germain Navicula cincta (Ehr.) Ralfs Ndviaila constans \ar. symmetrica Hust. Navictihi aispidata Kiitz. Naviada eli^ineusis var. lata (M. Perag.) Patr. Naviada gregaria Donldn Naviada menisctdus Schumann Navicula minu.scida \ar. muralis (Gmn.) L.-Bert Navicida jutptda Kiitz. Navictila radiosa Kiitz. Navicula tripunctata (OF. Miill.) Bor\' Navicula tripunctata \ar. schiz-oneiiwidcs (V.H.) Patr. Naviada trivialis L.-Bert. Navicula vciwta Kiitz. Nridium affinc (Ehr.) Pfitz. Ncidium did>ium (Ehr) Cl. Nitzschia acicularis (Kiitz.) W.Sm. Nitzschia amphibia Gnm. Nitz-schia calida Grun. Nitz.schia communis Rabh. Nitzschia constric-ta (Kiitz.) Ralfs Nitzschia di.ssipata (Kiitz.) Gnm. Nitzschia fonticola Gnm. Nitzschia Jnistulum (Kiitz.) Grun. Nitzschia hantzschiana Rabh. Nitzschia inconspicua Gnm. Nitzschia linearis (Ag.) W. Sm. Nitzschia microce))hala Grun. Nitzschia palea (Kiitz.) W. Sm. Nitzschia si^moidca (Nitz.) W. Sm. Nitz-scliia std)tilis Gnm. Pinnularia appcndiculata (Ag.) CI. Plcurosireek. In the Damoin- Ri\er stiid\' Aclinantlics inlnutissiina was the most important taxon with an ISI \alue of 44.4, followed bv Nitzschia dissipata (5.12), Cyniljella microcephala (3.63), and CifmheUa affinis (2.62). Shannon-Wiener diversit)' values for all 24 samples ranged between 1.95 and 4.59. Diver- sit)' did not show any clear trends with regard to season or substrate tyjoe. The overall mean for the indices was 3.42, the median \alue being 3.57. These \alues are relati\el\' high and indic- ative of unpolluted water. Oiu" collections did not cluster well on the basis of habitat t\pe or season. However, there was a tendency for stands to cluster on the basis of the Terpy's Ranch versus L)tle Ranch Pre- serve collecting localities (Fig. 2). The upper- most cluster consists of samples from Terrv's Ranch, while the second cluster contains sam- ples from the Lvtle Ranch Preserve. The third cluster has a mix of all sites, substrates, and seasons. The fall depositional sample from the Lvtle Ranch Preserve is an outlier. The reasons for the clustering b)' site seen in the top half of the cluster are unclear. Water chemistry' and temperature did not var\" greatlv between the sites during the year (Table 1). Likewise, insolation is approximatelv the same for both sections of the creek. Stream velocities, however, appear to be different. The creek at Lytle Ranch Presene is generallv slower, shal- lower (<15 cm), wider, and more meandering than the stream at Terry's Ranch where pools may reach depths of nearly one meter. The cluster shows a number of samples that paired b\- date of collection (Fig. 2). However, seasonalit)- was ver)- weak. The absence of sea- sonal changes is probably attributable to one or two factors. First, temperatiu'e changes tlu-oughout the year are minor, and changes in photoperiod alone are not enough to drive suc- cession. Second, storm events scour the creek bed occasionally and may keep the diatom assemblage in an early successional stage. The habitat t\pes sampled did not cluster separately, indicating they are fairly similar. Because of scouring events, the depositional areas initially sampled often had all sediments remoN'ed at later sampling dates and so consist PERCENT SIMILARITY 100 90 T M Nov. T R July T D/R July L D/R Apr. T D/R Apr. L R Feb. L R Apr. L R July T M Apr. L M July L D/R Feb. L R Apr. T R Apr. Fig. 2. Cluster diagram of 19 samples collected from Beaver Dam Creek. T = Terrv's Ranch, L = Lvtle 's Ranch Preserxe, M = macrophvtic vegetation (sedges), R = riffle, D/S = depositional area, .sediments, D/R = dejx)sitional area, rock scrapings. of rock scrapings, just as in the riffle areas. The one sample that consisted of sediment only (Lylile Ranch, November 1987, depositional area) clustered separately from all other sam- ples (see bottom line of cluster, Fig. 2). In summary, the diatom assemblages observed in Beaver Dam Creek consisted of cosmopolitan species common to other hard- water rixers. Seasonalit\' was minimal, as were the effects of habitat t\pe. LiTER.'\TURE Cited Blinn. D. \V., a. Fhkdf.hickskn, and V. Koin k 19.S(). Colonization rates and community stnictnre of diatoms on three different rock substrata in a lotic svstem. British Phycologicd Jouniiil 15: .30.3-.31(). Bush. D. E., and .S. C. Fishkk 1981. Metabolism of a desert stream. Freshwater Biologv' 11: .301-.3()7. CusiUNC,. C. E., and S. R. Risiifortm 1922.8 cm 0-40 0.0498 2 54 6 11 Ponderosa pine >22.8 cm 41-70 0.2083 33 287+ + 20 38 Ponderosa pine >22.8 cm 71-KK) 0.1239 33 92 13 33 Meadows 0.1016 11— 9— 5— 7 Oak 0-100 ().(K)44 4 0 1 1 Spruce 0-100 0.0056 0 1— 3 1 J^Sample sizes (telemetry fi,\es) are in parentheses. Expected use can be calculated from proportional use X sample size. Differences (P < .10) among habitats selected versus aviiilable are indicated l)y — if used less than expected and ++ if used more tli.u stage was selected less than expected during spring. No differences were noted for pon- derosa pine with 41-70% overstory canopv cover and 2.5-22.8 cm dbh across seasons. However, the structural stage greater than 22.8 cm dbh and 41-70% overstory canopy cover was selected more than expected during spring. Dense ponderosa pine ( >71% overstorx' canopv cover) 2.5-22.8 cm dbh was selected more than expected during winter and less than expected during summer. No differences were noted for dense ponderosa pine >22.8 cm dbh. 1992] TuHivt:Y Habitat Stratification 143 Discussion The highest level of stratification of habitats that added new information to use and selection patterns of Merriam's Turkeys in this study area was b\- DS\' and OCC. Despite statistical signif- icance of differences when habitats were strati- fied by DS\', SS, and OCC, trends in habitat selection were similar to analyses for which data were pooled across SS categories. Shaw and Smith (1977) noted apparent habitat selection b\- Merriam's Turkevs in Arizona when pon- derosa pine habitats based on diameter classes were ignored. However, pole-size ponderosa pine habitats were used more than other size classes b\' turkevs in Montana (Jonas 1966). Within our studv area, 12 ot the 372 ponderosa pine habitats had an average dbh of less than 15 cm (6 in); the lowest average dbh was 10.7 cm (4.2 in). Thirt\-se\en of the ponderosa pine habitats in the stud\ area had dbh greater than 30 cm (12 in), of which the majoritv" were in the 0-40% OCC category indicative of large over- mature trees. Most of the study area had been logged in the past one hundred \ears. Because excellent germination conditions for ponderosa pine in the Black Hills result in overstocked stands with reduced growth rates (Boldt and \'an Duesen 1974), ponderosa pine habitats larger than 30 cm dbh were rare. Ponderosa pine habitats in this study were representative of a narrow range of the potential tree dbh classes for ponderosa pine. However, they did represent the size classes of ponderosa pine throughout the Black Hills. The tests of the model for DSV x SS sug- gested good agreement between the model and observed use bv turkevs from a statistical point of \iew. These results suggest random selection of habitats when stratified by DSV x SS. Non- random selection of habitats had already been demonstrated. We also beliexe that stratifica- tion of habitats bv DSV x SS obscured biologi- cal patterns alreacK' demonstrated In the test of DSV X OCC. Many of the relationships of OCC were contrasted between high and low OCC. These results were pooled, resulting in the apparentlv good fit of the DS\' X SS UKxlel. Our approach to these anahses was hierar- chical in nature; and since patterns of habitat selection by turkeys had been demonstrated at higher le\els, it would not be prudent to ignore those biological patterns. Howexer, to ensure that no oversights were made, we made tests of hal)itat selection based on habitats stratified b\- SS, OCC, and SS x OCC. The test of the model for SS was not rejected. Tests of the model for OCC and SS x OCJC were rejected, but were influenced b\' the preponderance of the studv occupied b\ ponderosa pine (84%) and the range of dbh classes in the Black Hills. Interpre- tations of results from these latter tests were similar to tests of DSV X SS and DSV X OCC. Stratification of habitats bcNond that neces- sary' to depict the dispersion patterns of the animal decreases the sensitivit)- of tests and increases the probabilits of T\pe H error in the anahses (Alldredge and Ratti 1986). The effect of adding stratification factors is to dilute the sample sizes in indixidual cells, thus increasing the chance of Type H error. Apparent T\pe II errors occurred in the determination of habitat selection patterns when habitats were stratified b\ DS\' X SS X OCC. At the highest level of habitat stratification, apparent differences from expected use for three habitat categories disap- peared from the analyses. Acknowledgments This research was supported b\' the USDA Forest Ser\ice, Rocky Mountain Forest and Range Experiment Station; National Wild Turkev Federation; Black Hills National Forest; and South Dakota Came, Fish and Parks. We extend special thanks for the support and encouragement of Dr. A. J. Bjugstad (deceased). Technical assistance of R. Hodorff, T. Mills, C. Oswald, K. Thorstenson, K. Jacob- son, and L. Harris was appreciated. M. Green \'olunteered his time throughout this study, and R. Taylor allowed access to his property- for trapping and data collection. Dr. G. Hur.st, Dr. R. fonas, and H. Shaw reviewed earlier drafts of tliis manuscript. LiTER.ATURE CiTED Alldrf.dgf.. J. R.. and J. T Rvni 1986. Comparison of some statistical techuiejiii's for iuialysis of resource selection, jounial of Wildlife Management .50: 157- 16.5. Bf.wktt D. L. I9S4. Criizinn potential of major soils within the Black Hills of South Dakota. Unpublished master's thesis. South Dakota State Uni\ersit\, Brook- ings. 199 pp. Boldt, C. E., and J. L. Van Duf.sf.n. 1974. Sikiculture of ponderosa pine in the Black Hills: the status of our knowledge. USDA Forest Ser\ice Research Paper RM-124. Fort Collins. Colorado. 45 pp. 144 Great Basin Naturalist [Volume 52 Bkvant. F. C]., and D. Nisii 1975. Habitat use by Merriains Turkey in southwestern Utdi. In: L. K. Halls, ed., Proceedings of the Third National Wild Turkey Sym- posium 3:6-13. Texas Parks and Wildlife Department, Austin. Buttery. R. F., and B. C. Gillam. 1983. Forest ecosys- tems. Pages 43-71 in R. L. Hoover and D. L. Wills, eds.. Managing forested lands for wildlife. Colorado Division of Wildlife, in cooperation with US DA Forest Service, Rock-v Mountain Region, Denver, Colorado. 459 pp. Byeks, C. R., R. K. Steinhokst. and P. R. Kjuu.sman 1984. Clarification of a technique for analysis of utili- zation-a\ailability data. Jouniiil of Wildlife Manage- ment 48: 1050-1053. Cochran, W. G. 1963. Sampling techniques. John Wiley and Sons, Inc., New York. 413 pp. Jonas. R. 1966. Merriam's Turkeys in southeastern Mon- tana. Techniciil Bulletin 3. Montana Game and Fish Depiu^tment, Helena. 36 pp. LUTZ, R. S., and J. A. Crawford 1989. Habitat use and selection of home nuiges of Merriam's Turkey in Oregon. Great Basin Naturdist 49: 252-258. Mackey, D. L. 1982. EcologyofMerriam's Turkeys in south central Washington with special reference to habitat utilization. Unpublished m;ister's thesis, Washington State University Pullman. 87 pp. . 1986. Brood habitat of Merriam's Turkeys in south- central Washington. Northwest Science 60: 108-112. MOSTELLER, F., and A. Parunak. 1985. Identifying extreme cells in a sizeable contingency table: probabi- listic and exploratory approaches. Pages 189-224 in D. C. Hoaglin, F. Mosteller, and J. W. Tukey, eds.. Exploring data tables, trends, and shapes. John Wiley and Sons, Inc., New York. 527 pp. Nenno, E. S., and W M. Healy. 1979. Effects of radio packages on behavior of wild turkey hens. Journal of Wildlife Management 43: 460^65. Neu. C. W., C. R. Byers. and J. M. Peek 1974. A tech- nique for analysis of utilization-availability diita. Jour- nal of Wildlife Management 38: .541-545. Petersen. L. E., and A. H. Richardson 1975. The wild turkey in the Black Hills. Bulletin No. 6. South Diikota Game, Fish ;uid Parks, Pierre. 51 pp. Rose, B. J. 1956. An evaluation of two introductions of Merriam's Wild Turkey to Montiina. Unpublished master's thesis, Montana State College, Bozemtui. 37 pp. Scott, V. E., iuid E. L. Boeker 1975. Ecology of Merriam's Wild Turkey on the Fort Apache Indian Reservation. In: L. K. Halls, ed.. Proceedings of the Third National Wild Turkey Symposium 3:141-158. Texas Parks and Wildlife Department, Austin. Shaw, H. G. 1986. Impacts of timber harvest on Merriam's Turkey populations. Problem analysis report. Arizona Depiirtment of Game and Fish, Tucson. 44 pp. Shaw, H. G., and R. H. Smith 1977. Habitat use patterns of Merriam's Turkey in Arizona. Federal Aid Wildlife Restoration Project W-78-R. Arizona Department of Game and Fish, Tucson. 33 pp. Thomas, J. W. 1979. Wildlife habitats in managed forests: the Blue Mountains ofOregon and Washington. USDA Forest Service Handbook 553. U.S. Government Print- ing Office, Washington, D.C. 512 pp. Received 24 June 1991 Accepted 15 March 1992 Great Basin Naturalist 52(2), pp. 145-148 POLLINATOR PREFERENCES FOR YELLOW, ORANGE, AND RED FLOWERS OF MIMULUS VERBENACEUS AND M. CARDINALIS Robert K. Vickerv, |r. Abstract. — Red, orange, and yellow niorphs of Mimitltis verhetuwens and M. cardiimlis were field tested for pollinator preferences. The species are closely similar except that M. vcrhoiaccus flowers ha\e partiallv refle.xed corolla lobes, whereas M. ccirdinalis flowers ha\e fullv reflexed corolla lobes. On the basis of oxer 6()(X) bumblebee and hummingbird visits, highly significant (/; < .001) patterns emerged. Yellow, which is the mutant color morph in both species and is determined by a single p;ur of genes, was strongly preferred bv bumblebees ;uid strongly eskewed by Innnmingbirds in both species. Orange and, to a lesser extent, red were strongK preferred b\ hummingbirds but eskewed by bumblebees in both sjiecies. Thus, strong, but partial, reproductive isolation was observed between the yellow mutants and the orange- to red-flowered populations from which they were derived. Color — yellow versus orange iind red — appeared more iniportant than shape — piirtiallv reflexed versus fullv reflexed corolla lobes — in determining the preferences of tlu- guild of pollinators in tliis particular test environment for Mimulus vcrhenaceiis and M. cardinalis. Kl'ij words: Mimulus, spcciation, flower colors, pollinator preferences, bun^lAcbees, luaninin^hirds. How mucli of a change in flower color ancl/or shape is enough to lead to a change in pollinators and hence to reproductive isolation and poten- tially to speciation? The flower color and shape nioq^hs o^ Mimulus verbenaceus Greene and M. cardinalis Douglas provide an excellent system for addressing this intriguing question. Materials Mimulus verbenaceus and M. cardinalis are tspicallv bright red flowered and hiuiuningbird pollinated. However, yellow-flowered morphs occur in M. verbenaceus, e.g., in a population at N'assey's Paradise, Grand Canyon, Arizona, and in M. cardinalis populations, e.g., on Cedros Island, Baja California, Mexico, and in the Siskyou Mountains, Oregon. My experimental hybridizations show that yellow is due to a single pair of recessive genes that limit the floral anthocyanins to small dots in the corolla throat. Intermediate, orange-flowered forms are known in M. verbenaceus, specificallv the pop- ulation at Yecora, Sonora, Mexico. And, an intermediate, orange-flowered form of M. car- dinalis was obtained bv repeated cycles of selec- tion. In both cases orange is due to a single pair of quantitative genes that reduce the amount of anthocyanin pigments in the corolla lobes. Thus, parallel series of red, orange, and vellow color forms are available for both M. ver- benaceus andM. cardinalis (Table 1). Mimulus verbenaceus and M. cardinalis are similar, closely related species in section Enjthranthe (Grant 1924); however, their flow- ers differ in shape. Those of M. verbenaceus have only the upper pair of corolla lobes sharplv reflexed, giving the flowers a partiallv tubular aspect. The side pair of lobes and the labellum curve gently forward forming a bee landing [)lat- form. Flowers of M. cardinalis have both the upper and side corolla lobes shaq)K' reflexed, giving the flowers a fully tubular shape. The labellum is thrust fonvard and is fokk-tl on itself forming a ridge instead of a landing platform. Shapes of the flowers of both species would seem to invite hummingbirds. Flowers of M. verbenaceus but not those of M. cardinalis would appear adaj)ted for bees as well. How- ever, flowers of all three color moq^hs of both species showed no reflectance patterns in the ultraviolet, that is, no putative bee nectar guides. Thus, flower shapes of A/, verbenaceus and M. cardinalis are similar in some respects but differ in others of potential significance to pollinators. Department of Biolog\', University of Utah, Salt Lake CAW. Utah 841 IS 145 146 Great Basin Naturalist [Volume 52 Plan The effect of flower color and flower shape on pollinator preferences will be addressed stepwise. First, pollinator preferences for color — red, orange, and yellow — will be ascer- tained for M. verhenaceus plants onl)', holding flower shape constant. Second, red-, orange-, and yellow-flowered M. cardinalis plants will be added to the experiment. Are pollinator prefer- ences for red, orange, and yellow flowers of M. cardinalis the same as for those of the M. ver- henaceus series? Note that the pigments are identical (Vickery 1978). Or, does the difference in corolla shape between the two species lead to a difference in pollinator preferences? Methods Seeds for each of the six populations of the study (Table 1) were collected in the wild or harvested from transplants brought into the greenhouse except those of orange M. car- dinalis, which were obtained by selection. A large population of red M. cardinalis from Cedros Island was grown and the most orange- red flowered plant self-poUinated. Its progeny included several orange-flowered plants. Prog- eny of these plants were grown and found to breed true for orange and were used as the source of seeds for the orange M. cardinalis moiph. Seeds of the sLx populations were sown in early April 1988 in the University of Utah green- house, following which seedUngs were trans- planted into 4" plastic pots and grown to flowering. Pots were placed in plastic travs to facilitate bottom-watering, plants being ran- domly arranged as to flower color. When plants began flowering, they were moved outdoors to test pollinator preferences. Instead of using Red Butte Canyon Natural Research Area as before (Vickery 1990), with its relative paucity of pollinators, I scattered the plants on a lawn adjacent to native gambel oak clumps at the mouth of Parley s Canyon of the Wasatch Mountains in an area rich in pollina- tors. Some 50 to 100 plants of each color morph of M. verhenaceus made up the artificial popu- lation of the first part of the experiment. Some 50 to 100 plants of red and of orange M. car- dinalis plus 20 plants of yellow A/, cardinalis (all that were available) were added to the M. ver- Tablf, L Origin of populations studied. Mimulus verhenaceus Greene Vasscij's Paradise, Grtuid Caiivon, Arizona, USA, elev. -650 m Red moq^h = culture number 14,088 Yellow morph = culture number 14,089 Yrcora, Sonora, Mexico, elev. —1,550 m Orange = culture number 13,256 Mimulus cardinalis Douglas Isia Cedros. Baja California, Mexico, elev. -100 m Red moq^h = culture number 13,106 Yellow morph = culture number 13,2.50 Orange = culture number 13,249 (obtained by selection from the red moiph) henacens plants for the second part of the exper- iment. Pollinator visits to the flowers were observed and recorded for an average of \Vi hours per observation period for 15 periods for each of the two parts of the experiment (Tables 2, 3). Time of day of the observations was varied to be sure of noting all the different kinds of \isitors. To count as a visit, a hummingbird had to thrust its beak into a flower. A bee had to land on the flower and crawl into the flower far enough to brush the stigma and anthers. A fly, butterfly, etc., had to walk on the reproductive structures. The numbers of flowers rather than plants of each color of each species were recorded for each observation period. For analvsis of visits, chi-square tests were Rm for each obseivation period for each part of the experiment. The null hyj^othesis was that hummingbirds or bumblebees (very few flies, butterflies, etc., visited the flowers and were not listed) would visit the three colors of flowers of M. verhenaceus in the first part of the experi- ment and the three colors of M. verhenaceus and M. cardinalis in the second part of the experiment in proportion to the mmibers of those flowers in the experimental population (Tables 2, 3). If the overall chi-square value for a period of, for example, bee visits to M. ver- henaceus or hummingbird visits to M. cardinalis indicated a significant deviation from expected values, then the frecjuencv of \isits to each color was inspected. Those high or low enough that their term in the chi-square equation was large enough b\' itself to produce a significant devia- tion at the 5% level were considered to be significant (Tables 2, 3). 19921 MiMUIA'S FOLIJNATOH PREFERENCES 14' TablK 2. Pollinator pifffrencL'S for rt-d. orange, or \x'llow noweis ol Mimulus rcrhciuiccii.s in 19S8. Numbers of flowers Bumblebee visits Hummingbi ird visits Month:cla\:time Red Orange Yellow Red Orange Yellow P Red Orange Yellow P 7:26:1630 48 56 70 28i" 523T 1984- <.001 0 3 0 <.100 7:29:0745 56 91 74 30 50 58 <.200 0 SIT 29 <.010 7:30:0710 46 79 114 24 67 67 <.010 55T 66 70 <.010 8:02:1640 85 77 74 3i 8ST 53 <.001 27 49 27 <.010 8:03:0630 92 101 133 53 99T 81 <.()01 33 79T 36i <.001 8:03:1.540 120 117 172 3U 74 209T <.()01 lOOi 24 IT 183 <.001 8:04:0640 S6 73 178 (U 5 52T <.0()] S3 145T 170 <.001 8:05:0715 120 UK) 169 33i 71 125 <.()01 9i 77T 28i <.001 8:05:1645 126 104 174 12i 22i 126T <.001 36i 149T 92i <.001 8:05:1830 126 104 174 5i 4i 73T <.001 75 150T 82i <.001 8:06:0uiul spliilus hninnert.s. Journal of Mammalog)' 72: 583-600. Received 8 JaniKinj 1991 Accepted 18 April 1992 Great Basin Naturalist 52(2), pp. 160-165 NEW GENUS, APLANUSIELLA, AND TWO NEW SPECIES OF - LEAFHOPPERS FROM SOUTHWESTERN UNITED STATES (HOMOPTERA: CICADELLIDAE: DELTOCEPHALINAE) M. W. Nielson' luid B. A. Haws" Abstract. — A new genns, Aplaimsk'lla (type-species, Aplanusidla utahensis, n. sp.) and bA'o new species, A. ittahemis and A. calif onriensis , are described antl illustrated. The two species are allopatric and coexist on the same host genus, (Atriplex) with members of a closely allied leafliopper genus, Aplamis. Notes on distribution of hosts and leaflioppers as well as leafliopper intergeneric relationships are also given. Ki'ij words: leaflioppers. new species, new gentis, Cicadcllidae, Aplanusiella, distrihntion. hosts. In a 1986-89 suney of rangeland leafliop- pers of Utah (Haws et al. 1989), two populations were taken from Atriplex spp. and tentatively identified as members of the genus Aplamis. One population was later identified as Aplamis alhidus (Ball) from shadscale, Atriplex con- ferfifolia (Torn & Frem.) Wats. The other pop- ulation was collected from four- winged saltbush, Atriplex canescens (Pursh) Nutt. and is described herein as a new genus and new species closely allied to Aplamis. An additional new species is also described from specimens collected in California on Atriplex sp. Notes are given on the ph\1:ogeography of the host genus, Atriplex, the distribution of the two genera, and their taxonomic and host relationships. The general habitus (form and color pattern) of the component populations are so remark- ably similar that it is likelv that additional mate- rial of the new taxa will be found in other repositories. Only after dissection and examina- tion of the male genital structures will their tnie identity be revealed. Moreover, it is probable that additional new species will come to light after more thorough collecting is done on Atriplex spp. in southwestern United States and northeni Mexico. This assimiption is based on two additional populations of female specimens in hand from Nexada and California for which males are presently unknown and are required for definitive generic placement. The female seventh sternal characters appear to place these populations in the new genus (sensu .stricto). Populations of these groups are rather rare in Atriplex host areas of the high- to low-desert regions of western North America. Aplanusiella, new genus T\TE SPECIES. — Aplanusiella utahensis, n. sp. Small, rather slender species. Related to Aplamis Oman but smaller and with distinctive nicile genital characters. General color light yellow to ivory with numerous, nearly concen- tric, tiny rufous spots on forewings, spots not usually forming lines as typically present in Aplamis, large spots in claviis and in apical crossveins of costa fonned by aggregation of smaller spots, pronotum and scutellum some- times with tiny spots. Head narrower than pronotum, anterior margin obtusely angled and rounded to front, crowii produced mediallv to about one and one- half times length next to inner margin of eve, disk somewhat depressed in middle but lacks transverse depression before apex as in Aplamis; pronotum and scutellum as in Aplamis; fore- wings with imier anteapical cell open basally, appendix well de\ eloped; cKpeus and cKpellus as in Aplamis. Male pvgofer with macrosetae in apical half and with prominent caudoventral spine, some- times crossing over in caudal view; aedeagus small, base large in lateral \iew, apical htilf narrow, tubular, sometimes with smdl angulate protrusion at base of shaft on dorsal margin, gonopore subapical on ventral margin; connectiv e Monte L. Bean Museum. Brigham Young University. Provo. Utah S4602. Department of Biolog)-, Utah State Universitv-, Logan, Utah 84322. 160 1992] New Genus, Apianusieija 161 short, Y-shaped, articuhitrd with acdeagus; st\ie hroad, apophxsis short: plate trianpilate with row of niacrosetae subinarginalK and row of microsetae marginally, female seventh sternum with short projection medially on caudtJ margin. Two aliopatric species are known that occur in the southwestern states of Utah and Califor- nia on desert shrubs of the genus Atriplex. Aplanusiella can be distinguished from Aplantis b\ the sniiiller size, by the absence of a preapical depression on the crown, by the presence of a prominent caudoventral pvgofer spine, by the smaller aedeagus that lacks apical processes, and by the female seventh sternum that has a more distinctive spatulate process on the middle of the caudal margin. Aplanusiella utahensis, n. sp. Figs, la-ll Length. — Male 3..5-3.75 mm. female 4.00- 4.20 mm. General color pale yellow to ivor)' with numerous, nearly concentric, tiny nifous spots on forewdngs, large aggregate spots on apex of clavus and in apical crossveins of costa, some- times with few similar spots on pronotum and scutellum. Related to AplamisieUa californien- sis, n. sp., but with distinctive male genital and female seventh sternal characters. Male. — Pygofer in lateriil view with long, stout caudoventral process that sometimes crosses its counteipart in caudal view, but usu- ally closely appressed to caudal margin of pygo- fer (Fig. lb); plate long, triangulate with uniserate niacrosetae submarginallv and uniser- ate microsetae marginallv on outer margin (Fig. Ic); st)'le in dorsal view long, broad in basal 2/3, apophysis short, curved and pointed apically (Fig. Id); connective short, Y-shaped (Fig. le); aedeagus in lateral view short, ventral margin abruptly angled near middle, broad basallw shaft narrow, tubular with basal triangulate pro- jection on either side of dorsal margin, gono- pore subapical on ventral margin (Figs. If-lk). Ft:MALE. — Seventh sternum broadly exca- vated on caudal margin, with prominent median spatulate process (Fig. U). HOLOTYPE (male).— UTAH: Daggett Co., Browns park, Pyke plots, roadside, 12.\T.1987, four-winged saltbush, Atriplex canescens, B. A. Haws (CAS). Paratvpes, 1 male, Daggett Co., Brown's park, 3.5 mi E Jams ranch, 26.\T.19S7, on four- winged saltbush, Atriplex canescens. Haws, Nelson (authors collection); 2 males. 1 female, San Juan Co., Div \alley, 8.IX.1987, four-winged saltbush, Atriplex canescens. B. Haws, A. Issa (USU); 2 males, 2 females, Uintah Co., Bonanza, 14.VII. 1975-3.IX. 1976, Afn>/ex canescens, G. E. Bohart (USU); 1 male. Grand Co., Jughandle Potash Rd., 19.Vni.l987, four- winged saltbush, Atriplex canescens, B. A. Haws, C. R. Nelson (BYU); 1 male. Grand Co., Colorado River, Hwy 128, 6 mi NE jet. Uwy 191, 26.V.19H7, Atriplex canescens, B. A. Haws.'C. R. Nelson (USU). Remarks, — This species can be distin- guished from calif orniensis, n. sp., by the longer caudoventral pygofer process, by the abruptly angled ventral margin of the aedeagus, b\' the presence of a small ba.sal triangulate process on the dorsal margin of the aedeagal shaft, and by the prominent spatulate process on the middle of the female seventh sternum. The species is known from the eastern coim- ties of Utah bordering Colorado and is likely present in the western part of that state and in northern Arizona where the host occurs. Collec- tion dates suggest that the species has two gen- erations per \'ear and presuiuabK' cnerwinters as eggs on its host. Aplanusiella californiensis, n. sp. Figs, liii-ls Length. — Male 3.30-3.50 mm, female 3.60^3.80 nmi. General color as in A. titahensis, n. sp., and related to that species but with distinctive male genital and female seventh sternal characters. Head similar to utahensis except not as pointed apicallv Male. ately long caudoventral process that usualK crosses its counteqoart in caudal \iew, not closely appres.sed to margin of pygofer (P'ig. Im); plate long, triangulate, with row of mar- ginal micr().setae and submarginal niacrosetae (Fig. In); .style in dorsal \iew long, narrow, apophysis sliort, ol)li(juel\' tnmcate apicalK (Fig. lo); aedeagus in lateral view short, \entral margin gradualK' curved, apical third tubular broad basalK in ventral view, tapered toward apex, gonopore subapical on ventral margin (Figs. lj>-lr). Fe.\L\LE. — Seventh sternum with truncate caudal margin except for sliort, median process (Fig. Is). HOLOTYPE (miile). — CaLIFORNL\: Riverside Co., Indio, 12.1.1988, Atriplex sp., G. N. -Pv gofer in lateral view with nioder- 162 Great Basin Naturalist [Volume 52 Figs, la-ll. Aplfinusk'Ua utahensis, n. sp.: la, head pronotum, and scutellnm, dorsal view; lb, male pygofer, lateral view; Ic, right plate, ventral view; Id, right style, dorsal view; le, connective, dorsal view; If, aedeagus, dorsal view; Ig, same, lateral view; Ih, same (enlarged), .showing triangulate process, lateral view; li, same (showing variation), lateral \ie\v; Ik, same (enlarged), showing apex of aedeagus, ventral view; 11, female seventh sternum, ventral view. Figs. Im-ls. Aplanmiella calif omiensis, n. sp.: Im, male pygofer, lateral view; In, right plate, ventral view; lo, right style, dorsal view; Ip, aedeagus, lateral view; Iq, same, ventral view; Ir, same (enlarged), showing apex of aedeagus, ventral view; Is, female seventh sternum, ventral view. 1992] New Genus, Aplanusieija 163 Figs. 2a-2f, 2in. Aplanus pauperciilus (Ball): 2a, nude pvgofer, lateral \iew; 21). right plate, ventral view; 2c, aedeagus, dorsal view; 2d, same, lateral view; 2e, right sUle, dorsal \iew; 2f, connectixe, dorsal \iew; 2m, female seventh sternum' ventral view. Figs. 2g-21, 2n. Aplanus albidns (B;ill): 2g, male pvgofer, lateral view; 2h. right plate, ventral view; 2i, aedeagus. dorsal \iew; 2j, same, lateral view; 2k, right style, dorsal view; 21, connective, dorsal view; 2n, female seventh sternum, ventral view. 164 Great Basin Naturalist [Volume 52 Oldfield (CAS). Parat)pes, 2 males, 6 females, same data as holotype (OSU); 5 males, 16 females. Imperial Co., Brawlev, 23.VIII.1983, Atriplex .sp., J. Williams (OSU, BYU). Remarks. — This species can be separated from utahensis by the shorter caudoventral pvgofer spine, by the smoothly curved ventral margin of the aedeagus, by the lack of a basal process on the aedeagal shaft, by the broader base of the aedeagus in ventral view, and by the truncate caudal margin and shorter median pro- cess of the female seventh sternum. This species is knowTi from southern Califor- nia on Atriplex (species unknown) at elevations below sea level. Collection dates suggest that the species overwinters in the adult stage and ma\' have as many as three generations per year. Aplanus Oman Aplanus Onuui, 1949:138. Tvpe species, Eutctfix paiipcrctihis Ball. Only two species are known in the genus, both assigned by Oman (1949). Crowder (1952) treated the group with a key to species, rede- scriptions, and illustrations of the genital char- acters. The range of^ Aplanus is much broader in western United States than the presently known range o{ Aplonusiella. Characters are given for Aplanus pauperculns (Figs. 2a-2f, 2m) and Aplanus aUndus (Ball) (Figs. 2g-2l, 2n) to show generic relationships between them and species of AplanusieUa. In Aplanus the pygofer lacks the caudal spine, and the aedeagus is alxnit twice as long with distinctive terminal processes. The female seventh sternum lacks the obvious median caudal process that is present in AplanusieUa. Ball (1900) reported that shad- scale, Atriplex eon feiii folia (Torn & Frem.) Wats., was the host of Aplanus alhidus. The specific host of A. pauperculns is yet unknown. Phytogeographv o{ Atriplex Four-winged saltbush (Atriplex eanescens) is endemic to western North America. Its range extends from southern Canada to northern Mexico. Shadscale (Atriplex conferiifolia) is also endemic, but its range is more restrictive within western United States (Stutz and Sanderson 1979, 1983, Sanderson et al. 1990). Both species produce hybrids between themselves and other species of Atriplex. However, autopk)idy is the most common genetic mechanism in both spe- cies, which have produced a number of races throughout their range. These races and other ecotypes have been identified and mapped by these workers. The biogeographical relationships between Aplanus and AplanusieUa species and their host species are poorly knouai. Although hosts have been identified for two leaflioppers (Aplanus albiclus and AplantisieUa utahensis) of the four known species, nothing is known about the others nor has preference, if any, of these leaf- hoppers for races or ecotypes been studied in Atriplex. The role of Atriplex in the evolutionary development and speciation of the group is like- wise unknown. Deposition of type specimens The holotvpe specimens of AplanusieUa utahensis and AplanusieUa califomiensis are deposited in the California Academv of Sci- ences, San Francisco (CAS); parat\pes are in Oregon State University, Corvallis (OSU), Utah State University, Logan (USU), and Monte L. Bean Museum, Brigham Young University, Provo, Utah (BYU). Acknowledgments We thank Paul W. Oman, Oregon State Uni- versit\', Corvallis, for loan of material of Aplanus and C. Rilev Nelson, Universitv of Texas, Austin, for his assistance in collecting material in Utah. We iilso appreciate helpful comments by H. Derrick Blocker, Kansas State University, Man- hattan, and Paul H. Frevtag, University of Ken- tuck"\', Lexington, who reviewed the paper. This studv was supported in part by endowanent funds from the Monte L. Bean Life Science Museum, Brigham Young University, Provo, Utah, for which we are grateful. Literature Cited Ball. E. D. 1900. Some new Jassidae from the Southwest. C:anadi;in Entomologist 32: 200-20.5. (^ROWDKR, II. \V. 1952. A re\ision of some phlepsiuslike genera of the tribe Delttxephdini (Homoptera, Cicadellidae) in America north of Mexico. Kansas Uni- versitv Science Bulletin 35: .309^541. H.\ws, B.'a., G. E. Boh.'KRT. C. R. Nelson, ;uid D, L. Nelson 1990. Insects and shnib die-off in western states: 1986-1989 survey results. Pages 127-151 in E. D. McArthur. E. M. Romne\. S. D. Smith, and P T. Tueller, eds., Proceedings — Svmposium on Cheatgrass Invasion, Shrub Die-off and Other A.spects of Shrub Biolog)- and Miuiagenient. Las Vegas, Nevada, .5-7 1992] New GE>i{JS, Aflawsieija 165 April iyS9. I'SDA F'ori'st Scnicc. (Jeiieral IVcliiiical Arid land plant tx^sonrces. Pr(K-efdini;s of tlu- Intcrna- Report INT-276. 351 pp. tional Arid Land Conference on Plant Resonrccs. Oman, P. W. 1949. The Nearctie leiiflioppers. A generic International Center for Arid and Seini-iirid Land classification and check-list. Memoirs of the Entonio- Studies, Texas Tech Uni\ersitv. Liihhock. 621 pp. logical Society of Washington. . 1983. EvoKitionarv studies oi'Atriplcx: chromo- Sanukkson, S. C'., H. C. Silt/, and E. 1). McArtihh some races of A, confertifolid (Shad.scale), American 1990. Geographical differentiaHon in Atriplcx am- Journal of Botany 70:' 1536-1547. fertifolia. American Journal of Botany 77: 490-498. Stutz, H. C, iind S. C. Sanderson. 1979. The role of pol\ploid\ in theeyolutionofAfn/jfevtYniesren.s-. Pages Received 11 Fehnian/ 1992 615-621 in J. R. Goodin and D. K. Northington, eds., Acccf)te(l 12 May 1992 Creiit Basin Natunilist 52(2), pp. 166-173 SUMMER HABITAT USE BY COLUMBIAN SHARP-TAILED GROUSE IN WESTERN IDAHO Victoria Ann Saab and Jeffrey Sliavv Marks" Abstra(ti" — We shidiecl smnnier habitat use by Columbian Shaip-tailed Grouse {Tytnpuuuchus pJuisiancllus co- hunhiaims) in western Idaho during 198.3-S5. Vegetative and topographic measurements were recorded at 716 locations of 15 radio-tagged grouse and at 180 random sites within the major vegetation/cover types in the study area. The mean size of summer home ranges was 1.87 ± 1.14 km". Of eight cover types identified in the study area, individual grouse used the big sagebrush {Artcviisia tridentata) cover type more than or in proportion to availability, the low sagebmsh [A. arhusaila) type in proportion to availability, and avoided the shrubby eriogonum (Eriooonum spp.) tyjie. Characteristics of the big sagebmsh cover tyj^e that Sharp-tailed Cirouse preferred include moderate vegetative cover, high plant species diversity, and high stnictural dixersitv. Grouse used areas of dense cover (i.e., mountiiin shrub and riparian cover tyjjes) primarily for escape cover. Compared with random sites, grouse selected areas with (1) greater horizontal ;uid vertical cover, (2) greater canopv coverage of forbs tyj^ically decreased by livestock grazing, (3) greater density and canopy coverage of arrowleaf balsamroot (Balsamorhiza sagittata), and (4) greater canopy coverage of bluebunch wheatgrass (Agroptjron spicatum) in the big sagebmsh cover type in 1984 ;uid the low sagebrush cover type in 1985. The importance of the native perenniiils arrowleaf biilsamroot and bluebunch wheatgrass became apparent chiring a drought year when many exotic annuals dried up and provided no cover. Overall, grou.se selected vegetative communities that were least modified bv lixestock grazing. Key words: Tympanuchus phasi;uiellus columbianus, C(>luml>itin SJiaiy-taiJcd Gnnise. Idaho, stnnuwr habitat charac- teristics, nmnaocment . Coliinibian Shaip-tmled Grouse {Tynipa- nuchiis phasianellus columbianus) have declined in both numbers and distribution since European settlement, currently occupying <10% of their former range (Miller and Graul 1980). Degradation of native habitat by live- stock grazmg and agriculture are thought to be major factors in this decline (Yocom 1952, Aldrich 1963, Zeigler 1979). Overgrazing reduced bunchgrasses and perennial forbs that are important components of nesting and brood-rearing habitat (Yocom 1952, Jewett et al. 1953, Klott and Lindzey 1990). Conversion of range to cropland destroyed nesting and brood- rearing habitat and deciduous shrubs that are critical for winter food and escape cover (Zeigler 1979, Giesen 1987, Marks and Marks 1988). As a result, Columbian Sharp-tiiiled Grouse were designated as a candidate species for listing as federally threatened/endangered (Federal Reg- ister 1989). Quantitative information on home range size and habitat preferences of (Columbian Shaip- tailed Grouse throughout their range is lacking. especially data based on radio-tagged individu- als during the summer reproductive period (see Klott and Lindzey 1990). We studied Colum- bian sharjDtails in areas with eight vegeta- tion/cover types. The primary objective of our study was to provide information on summer habitat preferences by Columbian Sharp-ttiiled Grouse. Study Area The 2000-ha study area is 23 km north of Weiser in Washington Countv; Idaho. Elevation ranges from 970 to 1188 m. Annual precipita- tion averages 39 cm. The springs and summers of 1983 and 1984 were relatively cool and wet, whereas those of 1985 were unusually hot and dry. Sharp-tiiiled Grouse had not been himted in the study area since 1974. Vegetation is characteristic of a sliRibsteppe communitv (Marks and Marks 1987a). The greatest proportion of the studv area (40%) was occupied bv the big sagebmsh (Artemesia trident (it a) cover t\pe; low sagebmsh (A. arhusndo) and shmbby eriogonum {Eriogonum Biology Department, Montana .Slate Univt-nsitv. Bo/cmaii, Montana 59717. Present address: USDA Forest Ser^nce, Intermonntain Ke M)Ttle Street, Boise, Idaho 8.3702. Di\nsion of Biological Sciences, University of Montana, Missonla. Montana .'59812, •arcli Station. .316 E, 166 19921 Sharp-tailed Grouse Summer Habitat 16- sphacrocephaluiii and E. thijiiioidca) Upes occupied 21 and 20%, respectively. The remain- ing 19% of the stud\- area was occupied bv' five other cover tvpes (see below). The big sagebnish cover t\pe was dominated bv big sagebrush, with lesser amounts of bitterbrush {Purshia tridentata) and low sage- brush. The greatest canopv coxerage of blue- bunch wheatgrass {Agropyron spicatuin) was found in this cover type; arrowleaf btilsamroot (BaJsanwrhiza sogittata)wds the dominant forb. Bulbous bluegrass was the most common her- baceous plant in the understor\' of the low sage- brush co\er t\pe with lesser amoimts of willoweed {Epilobium paniadatum), blue- bunch wheatgrass, and Sandberg's bluegrass {Poa sandhergii). The herbaceous layer of the shnibbv eiiogonum cover t\pe was relativelv sparse and dominated bv Sandberg's bluegrass. The mountain shrub cover type occurred in dense patches on hillsides; common species were bittercherr\' {Pnimis emarginatus), common chokecherr}' [P. virginiana), snow- brush ceanothus {Ceanothus vehitimis), and Saskatoon serviceberry {Amelanchier alnifolia) . The shrub layer of the bitterbrush (Purshia tridentata) cover type was almost exclusively bitterbnish, while the herbaceous layer was sim- ilar to that found in the big sagebrush t)pe. Riparian vegetation was dominated by Douglas hawthorn (Crataegus douglasii), with lesser amounts of wallow (Salix spp.) and Woods rose (Rosa woodsii). Bulbous bluegrass (Poa btdhosa), an exotic grass, was widespread throughout the study area. Plant nomenclature follows Hitchcock and Cronquist (1976). Two vegetation t\pes were almost exclu- sively comprised of nonnative vegetation. A small portion of the study area contained agri- culture, composed of dryland wheat and barley, and monocultures of intermediate wheatgrass (Agropyron interniedinni) seedings. The study area was grazed by livestock since at least 1900. Before about 1940, large bands of sheep were driven through the area. Since then, the major land use in the studv area has been cattle grazing. No livestock grazing occurred during this study. Methods Trapping and Monitoring Grouse were captured on dancing grounds using funnel traps, mist nets, and drop nets. Sex was determined 1)\' examination of crown feath- ers (Henderson et al. 1967) and age by exami- nation of outer primaries (Ammann 1944). ThirtA-eight grouse (28 males and 10 females) of 46 captured were fitted with solar-powered radio transmitters attached to Herculite pon- chos (Marks and Marks 1987b). Radios weighed between 13.5 and 14.5 g. Fifteen (13 males and 2 females) grouse provided data for home range and microhabitat analyses. The other 23 grou.se with radios were relocated for two months or less as a result of mortality (Marks and Marks 1987b) or dispersal from the stud\' area. Data from these birds were used in the microhabitat analyses but not in the calculation of home range size. Sample sizes were not large enough to compare habitat use or home range size between male and female grouse. Radio-tagged grouse were monitored from May to September 1983—85. Each time a grouse was located, it was flushed (hereafter these loca- tions are called flush sites). Flush sites sened as focal points for habitat sampling and for calcu- lation of home ranges. Grouse were located throughout the day and locations were stratified into four time intervals: sunrise to 0800, 0801 to 1100, 1101 to 1700, and 1701 to sunset. On average, each radio-tagged bird was flushed four days a week, once in each of the four time intervals. Habitat Sampling The stud\' area boundaiv was determined by grouse movements during 1983. C^cn-er tvpes were digitized and areas calculated for each t) pe using GEOSCAN (Software Designs 1984), a geographic information program. Flush sites were plotted and home range sizes (Mohr 1947) were calculated using the compute^- program TELDAY (Lonner and Burklialter 1986). ' Use vs. availabilih' of cover t\pes (i.e., macrohabitat) was assessed by (1) using the proportion of cover t\pes within each bird's home range, and (2) using the proportion of cover tyj:)es within a 1.2-km radius of the danc- ing ground at which each bird was captured. The 1.2-km radius around each of three dancing grounds (upper, middle, and lower) encom- passed 90% of all grouse locations. Flush sites within 50 m of a dancing ground during the spring and autumn display periods were omitted from macrohabitat analyses. We measured \egetation at each flush site (i.e., microhabitat) to estimate plant .species 168 Great Basin Naturalist [Volume 52 composition, frequency, percent canopy cover- age, and bare ground using a 20 X 50-cm frame (Daubenniire 1959). Five frames were read at each flush site: one at the approximate center and one in each of the four compass directions at randomly chosen distances of 2, 4, 6, or 8 m from the center location. Vertical structure of the vegetation was evaluated by a coxer board that was a 16.5 x 49.5-cm rectangle. The cover board was placed at the center of the flush site and read twice from 5 m away in each of the four compass directions while the observer was prone and standing, respectively. A total reading of 150 squares was possible from each compass direction. In total, five canopy coverage and four cover board measures were taken at each site. Other variables recorded at flush sites included (1) cover type, (2) distance to water, (3) percent- age of slope, (4) distance to nearest riparian or mountain shrub cover type, and (5) cover type where flushed grouse landed (landing site). We recorded vegetative and topographic measurements at randomly located sites to assess microhabitat avmlability in the cover t\pes used most bv grouse. Habitat characteris- tics were sampled with similar methods as described at flush sites. A total of 180 random sites were sampled during the study, 30 each month during Mav through Julv in 1984 and 1985. The number of random sites located in each cover type was based on the percentage of area occupied by that cover type in the study area. Canopy coverage and cover board read- ings were recorded at the origin and at points every 10 paces along a straight line until 20 readings were completed. Slope and distance to the nearest mountain shiub or riparian cover type were recorded onlv at the first, tenth, and twentieth frames of each random site. Data AnaK'sis Data were anab'zed with the Statistical Anal- ysis System (SAS Institute, Inc. 1982). Use- availabilit)' analyses of cover types were conducted with chi-s(juare goodness of fit tests (Neu et al. 1974) and Bonferroni z-tests (B\ers et al. 1984). Data were analyzed separately for each year and pooled when differences were not significant. For analyses of canopy coverage, each plant species was placed into one of 10 categories: ( 1) big sagebrush, (2) low sagebrush, (3) bitterbrush, (4) other shrubs, (5) arrowleaf balsamroot, (6) other composites, (7) non- composite forbs, (8) bluebunch wheatgrass, (9) bulbous bluegrass, and (10) other grasses. Non- parametric statistics (Mann-Whitney U- and Kruskal-Wallis tests) were used to anaK'ze canopy coverage and vertical stmcture because these data were not nonnally distributed (Con- over 1980). Vegetative measurements at flush sites from May through July were combined by cover tvjje and month for comparisons with data collected at random sites for the same period. All multiple comparisons were computed with Tukey tests (Zar 1974). The Shannon-Wiener index was used to calculate plant species diver- sity (Hill 1973). Proportions entered into the diversit)' formula were derived from the total number of plant species occurrences within the frames used to estimate canop\' coverage. The significance level for all tests was P < .05, and all tests of means were two-tiiiled. Means are fol- lowed by ± one standard deviation. Results Home Ranges and Macrohabitat Selection The mean size of summer home ranges was 1 .87 ± 1 . 14 km- (N = 15, range = 36-68 locations per grouse). Based on habitats within home ranges, three trends emerged from the use- availabilit)' analysis of coxer t\pes: (1) grouse used the big sagebrush cover t}pe more than or in proportion to availabilitv; (2) the low sage- brush cover t\pe was used in proportion to a\ailabilif\', and (3) the shrubby eriogonum and intermediate wheatgrass coxer txpes xvere avoided (Table 1). These trends xvere similar xvhether use-aviulabilit\' xvas assessed xxithin estimated home ranges or xxithin a fixed radius aroimd the upper and lower dancing grounds (Table 1). In addition, a single grouse from the middle dancing ground used the big sagebiTish coxer t\pe more than that expected bx' chance xxithin its home range and the fixed radius. Grouse were seldom found in the denser cover txpes, i.e., riparian and mountain shrub habitats. Hoxx'exer, thex used these coxer txpes as escape coxer in 77% of the cases xxhere the landing site of a flushed radioed bird xx'as obsened (N = 338). Microhabitat Selection Mean distance to xvater did not differ signif- icantly bet\x'een flush (.V = 297.6 ± 183.3 m) and random (.v = 295.9 ± 211.7 m) sites (F < .40), and no evidence xvas found that Shaip-tiiiled Grouse sought free xvater. The range of slopes 1992] Sharp-tailed Grousk Summer Habitat 169 Table 1. Sunnner hahitat usf-a\ailal)ilih analysis showing tli(- iniinl)er oi raclio-taggml (Columbian Sliarp-tailed Crouse using the major cover types more than ( + ), less than ( — ), or in projxjrtion to (NS)'' that expected by chance ', 1983-85. Cover types Home range NS 1.2-km fixed radius NS Upper dancing ground Big sagebnish Low sagebrush Shnibbv eriogonuni Mountain shrub Number of grouse Lower dancing ground Big sagebrush Low sagebrush Intermediate wheatgrass Number ot grouse Total number ot grouse 2 0 3 0 1 4 0 5 0 1 0 4 N = 5 7 0 2 0 3 6 0 2 ' N = 9 N = 14 0 0 5 0 0 5 0 5 0 1 0 4 8 0 I 0 1 8 0 6 3 ■'Not sigiiitkant, 'T < .05. used by grouse was 0-47%. Grouse used three classes^ of slope intervals (0-9%, 10-29%, >30%) in proportion to their availabilit\; with >95% of the use occurring on slopes <30% (Marks and Marks 1987a). Grouse did not show a strong preference for sites that were close to nioinitiiin shmb or ripar- ian \egetation except in 1985, the drought year. The mean distance to mountain shrub and ripar- ian habitats measured at flush sites {x = 151.5 ± 156.5 m) was farther than that measured at random sites (.v = 120 ± 99.7 m) in 1983 and 1984 (Mann-Whitney L'-test P < .04) but signif- icantly closer (flush sites, x - 84.4 ± 90.9 m) in 1985 (F< .0001). Vertical cover measured at random sites dif- fered significantly among cover types (Kruskal- Wallis P < .001). Mean cover board readings indicated that the bitterbrush cover tyjie pro- vided the greatest cover; big sagebrush, inter- mediate wheatgrass, and low sagebrush tyjoes ])ro\ided intermediate cover; and eriogonmn sites had verv little cover (Fig. 1). A drought during 1985 resulted in significantly less vertical cover in 1985 than in 1984 (Mann-Whitney li- test P < .01 ). However, the rank order of cover availabilitv was the same among all cover t\pes except intermediate wheatgrass, which de- creased substantiiillv in 1985. Eight\'-three percent of the flush sites for which microhabitat measurements were taken occurred in big and low sagebrush cover t\pes. \'egetative data on microsite use vs. availability- were evaluated onlv for big and low sagebrush cover types because sample sizes were too small for the other types. Vertical cover measured at flush sites dif- fered among years within big and low sagebrush cover types (Kmskal-Wallis P < .05). As noted at random sites, there was significantly less cover in 1985 than in 1984. A comparison of grouse flush sites with random sites revealed that grouse selected denser cover than that mea- sured at random sites (Fig. 1). The cover types used most by grouse, big and low sagebnish, had a higher diversitv of shrub, forb, and grass species than the otlier cover tvpes (Fig. 2). The big sagebrush cover type had the highest diversit)' of shnibs and grasses, and the low sagebrush cover tvpe had the highest diversity of forbs. Overall, the big sagebnish cover tyjDe had the highest stnictural heteroge- neity (measured as the coefficient of variation of canopv coverage and cover board readings). During 198.3-85, canopv coverage oi shnibs at grouse flush sites averaged about 9% in both big and low sagebnish cover types. Forb cover- age averaged about 30%, and grasses ranged from 28% to 32% canopv coverage in low sage- brush and big sagebrush cover tvpes, respec- tively. Overall, canopy coverage at flush sites was significantlv greater than at random sites due largelv to greater total forb coverage at flush sites (Table 2). (^onverselv, percentage of bare ground was less at flush sites than random sites in all cases (Table 2). Sites chosen by grouse in 1984 and 1985 had significantlv- higher arrowleaf balsamroot cover than did random sites. There was significantly higher canopy 170 Great Basin Naturalist [Volume 52 O RANDOM D FLUSH t 6 ^ ARAR ERIO COVER TYPES Fig. L Mean (± SD) cover board readings at random sites and Sharp-tailed Grouse flush sites in the major cover types (big sagebnish [ARTR], low sagebnish [ARAR], shrubby eriogonum [ERIO], intermediate wheatgrass [AGIN], bitterbrush [PUTR], 1984-85 (° = F < .001). Vertical tixis represents the number of boxes visible on the cover board (see Methods). 26- 24- 22 X 3. 20 >- (/) ' EC , liJ I 1^ LLI CL cn 6 (66) (67) (45)^5 .{24) COVER TYPES Fig. 2. Plant species diversit) (e" ) at random sites for shrubs, forbs, and grasses in the major cover tyjies (big sagebnish [ARTR], low sagebnish [ARAR], shrubby eriogonum [ERIO], intermediate wheatgrass [AGIN]), 1984-85. The total number of plant species sampled in each cover type is in parentheses. coverage of bhiebunch wheatgrass at grouse flush sites than at random sites in the big sage- brush cover ty|3e in 1984 and in the low sage- brush cover ty|)e in 1985. Canopy coverage at grouse flush sites in the big sagebrush type differed among years in five of six vegetative categories (Fig. 3). Bare ground increased while bulbous bluegrass, other forbs, and other composites decreased during the drought of 1985 as compared to 1983 and 1984. However, bluebunch wheatgrass increased in 1985, while the cover of arrowleaf balsamroot was not significantly different among years. Bluebunch wheatgrass and arrowleaf balsamroot are native perennials that are con- sidered decreaser species (Bhiisdell and Pechanec 1949, Evans and Tisdale 1972); i.e., they tvpicallv decrease or are eliminated under heaxy livestock grazing (Dyksterhuis 1949). Canopy coverage of decreaser forbs was signif- icantly greater at flush sites than at random sites in the big and low sagebrush cover types ( IVIarks and Marks 1987a). Discussion Summer home ranges for this subspecies in Colorado (Giesen 1987) and for other subspe- cies (Artman 1970, Christenson 1970, Ramhar- ter 1976, Gratson 1983) were sniiiller than we observed in this study. Differences in home range size were probably a reflection of habitat condition; larger home ranges were obsened in western Idaho, where decreaser forbs were lim- ited and historic livestock grazing apparently had a greater influence on the vegetation. From spring to fall, >90% of all grouse loca- tions were within 1.2 km of a dancing ground. Similarly, locations of Sharp-tailed Grouse in other studies were within 1.0 and 2.5 km of dancing grounds (Pepper 1972, Oedekoven 1985, Giesen 1987, Nielsen and Yde 1982). These results suggest that maintiiining habitats within 2.5 km of dancing grounds will provide summer habitat recjuirements for Shaip-tiiiled Grouse. Compared with other cover tyjoes, big sage- brush sites had a high diversit)' of shrubs, forbs, and grasses; the highest structural diversity; and the greatest canopx' coverage of perennial bimch- grasses. The sharptails" overall preference for the big sagebrush cover type indicated that they likely selected for habitat diversitv relative to surrounding areas. 1992] Sh.\hp-tailed Grouse Summer Habitat 171 T.^BLK 2. Mean can<)p\- coverage (%) of\'cgetativecateg()rie.siiil)igsagebnish (ARTR) and low sage! )ni.sli (ARAR) cover tvpes at Columbian Sliarp-tailed Grouse flush sites vs. random sites. Year 1984 1985 ARTR ARAR ARTR ARAR Vegetative Flush Random Flush Random Flush Random Flush Random category' (io7r (42) (21) (24) (107) (42) (21) (24) Big sagebrush 3.43 4.03'' 0.02 0.07 4.97 6.. -32 0.22 0.33'' Low sagebnish 0.21 0.49'' 5.45 7.. 84 0.55 0.79'' 7.03 7.88 Bitterlmish 1.52 1.02 0.86 0.17 2.76 l.w'' 1.15 0.88 Otlier shmbs 1.73 0.89 0.14 0.59'' 2.21 2.69'' 1.36 0.40 Total shrubs 6.89 6.43 6.47 8.67 10.49 11.84 9.76 9.49 Arrowleaf balsamroot 13.60 6.55'' 12.21 3.91'' 13.06 7.40'' 11.91 5.28 Other composites 7.05 3.78'- 5.14 2.95'' 2.90 3.33 3.02 3.19 Otlier forbs 12.76 15.3l'' 12.83 14.24 9.70 7.87 14.97 7.22 Total forbs 33.40 25.64'' 30.18 21.10'' 25.66 I8.6O'' 29.90 15.69 Bluebnnch wheatgrass 2.93 2.56'' 1.02 0.85 5.18 2.91 4.72 0.46'' Bulbous bluegrass 35.87 24.59'' 36.83 23.09 15.97 16.52 13.20 22. a3'' Other grasses 3.76 4.32 2.52 3.32 3.01 2.02 3.33 3.29 Tcjtal grasses 42.56 31.47 40.37 27.26 24.16 21.45 21.2,5 26.08'' Bare ground 23.93 35.93'' 28.05 42. 30'' 40.23 48.62'' 39.31 48.94'' ■'Sample .size (number ot trausecLs conducted in each tspe). 'Indicates significant difference (P < .05) in mean canopy coverage behveen flush and random sites withi ver tjpes. Slinibb\' eriogonum sites, which were strongK' axoided by grouse, contained a low di\ersit\ of forbs, and even in the absence of grazing proNided Rttle cover. Exchiding dancing grounds, Shaip-tailed Grouse studied else- where have exliibited similar selection against areas of sparse cover (Pepper 1972, Ziegler 1979, Klott and Lindzey 1990). The intermedi- ate wheatgrass cover type also was avoided by grouse. Grouse were particularly absent from intermediate wheatgrass during years with rela- ti\elv low numbers of grasshoppers. Mountain shrub, riparian, and bitterbnish habitats were used primariK as escape cover during spring and summer. Beginning in late siunmer, moimtaiu shrub and riparian plant spe- cies produced fniits that became an important part of the grouse diet (Marks and Marks 19S7a). Proximity to this shrubby vegetation ma\- not have been critical during earK" to mid- summer when the cover types preferred by grouse were providing adequate food and cover. Grouse were found closer to mountain shrub and riparian habitat than expected l)y chance only in the drought year (1985), when xertical cover decreased significantK' in all cover t\pes that were measured. Shaq^tails apparentK' selected areas least modified by lixestock grazing. Grouse locations were characterized by greater herbaceous cover and less bare ground than random sites. Studies of plant communities with and without gnizing indicate that areas with relati\eK- little bare ground are least modified b\- li\estock (.see 40 - a e / S.BAGR / 30 ^ y ^^ y?\ \ 20 - \ \ >POBU 10 - '^""'g'"--.,^ . ~-^OTFO -AGSP ~"OTCO ^' _^^Z-=-' "^ - k k 1 1 1 1984 YEARS Fig. 3. Comparison of canopy coverage at Sharp-tailed (Jrouse flush sites in tlie big sagel)nish co\er t%pe in western IiliJio. 198.3-85. On each line different letters indicate that corresponding means are significantK' different at P = .05. (BAGR = bare ground. POBU = bulbous bluegrass, BASA = arrowleaf b;i]samroot, OTFO = other forbs, AGSP = bluebiuich wheatgrass, OTCO = otlier composite forbs.) 172 Great Basin Naturalist [Volume 52 Holechek et al. 1989). When eoinpared with random sites, grouse locations had significantly higher proportions of forb species that decrease from overgrazing (Dyksterhuis 1949). In partic- ular, grouse preferred microhabitats with greater abundances of arrowleaf btilsamroot and bluebunch wheatgrass, two plant species that ty}3icallv decline with overuse by livestock grazing (Blaisdell and Pechanec 1949, Evans andTisdale 1972, Muegglerand Stewart 1980). These native perennials are major components of later serai stages (Hironaka et al. 1983). The presence of arrowleaf balsamroot and bluebunch wheatgrass as cover plants during a drought year is especially noteworthy. These plants are particularlv drought resistant (Tisdale and Hironaka 1981, \Vasser 1982). Bulbous blue- grass, the most abundant and widespread grass in the study area, is an introduced perennial with root systems that die each year; it is virtu- ally nonexistent during years of low moisture (Monsen and Stevens, in preparation). Indeed bulbous bluegrass contributed lower cover values in 1985 than in 1983 and 1984 (years with average moistiu-e) (Table 2). In contrast, cover of bluebunch wheatgrass was similar among those years. In the absence of nati\e perennials, grouse would not have had as much cover dining drought years. The loss of these important cover plants may have contributed to the disappear- ance of Columbian Shaq:)-tailed Grouse from large portions of their historic range. CONCLUSlOxNS AND MANAGEMENT Implications Ciiven the widespread decline of the Colum- bian Sharp-tailed Grouse and the fragmented nature of extant populations, consenation of all potential sources of genetic variation should be a critical concern to managers. Maintenance of shniljsteppe coiumunities in advanced serai stages is especially important for con.servation of summer habitat in the Intermountain region. Habitat features that characterize occupied habitats in western Idaho are flat to rolling rangeland in relatively good condition with a diversity of native shmbs, forbs, and grasses. Native perenniiils arrowleaf balsamroot and bluebunch wheatgrass are critical for cover during a drought year. Also important is riparian vegetation and numerous patches of mountiun shrubs for escape cover and late summer food. These habitat characteristics suggest that Columbian Sharp-tailed Grouse are an indica- tor of good range condition in the mesic shnibsteppe of the Intermountain region. Federal land management agencies are directed to conserve candidate species and their habitats and to avoid actions that mav cause the species to become listed as federally threat- ened/endangered. Conservation efforts for Columbian Shaqo-tailed Grouse, a candidate species, must include protection and enhance- ment of habitats that are occupied by the sub- species throughout their range, especially disjunct populations in jeopardy of extirpation. The success of attempts to improve their cur- rent status is dependent on reducing distur- bances that may damage the natural diversity of shrubsteppe habitat (e.g., overgrazing by live- stock and agricultural development). Protecting habitats within 2.5 km of dancing grounds is critical for mmntainence of summer habitat. Suitable habitats for reestablishment within their historic range need to be identified. However, reestabHshment efforts for this native species should not take precedence over pres- ervation and restoration of habitats that cur- rently support sharptails (cf. Griffith et al. 1989). Acknowledgments We thank A. Sands, L. Nelson, S. Mattise, R. Eng, T Lonner, R. Autenrieth, R. Nelson, and J. Connelly for their contributions to the study, and the G. Tarter and T Nelson families for granting access to their lands. We are also grate- ful for the field assistance provided by B. Czech, J. Berr)'hill, S. Lisle, and R. Morales. J. Craw- ford, C. Groves, K. Giesen, and T. Martin pro- vided useful suggestions for manuscript improvement. The research was funded bv the U.S. Bureau of Land Management; additional support was provided bv the Idalio Department of Fish and Game and Montiuia State Universit)'. . - Literature Cited A1.DRICH, J. W. 1963. Cieographic orientation of American Tetraonidae. Joiiniiil of WikUife M;uiagenient 27: 529- .545. Ammann. G. a. 1944. Determining the age of Pinnated and Shaqi-tailed Gronses. |onrnal ot Wildlife Miuiagement 8: 170- 17 1. .'Viri'MANN, J. W. 1970. Spring and snnmier ecology- of the Shaq^-tciiled Grouse. Unpublished dissertation. Uni- versity of Minnesota, St. Paul. 129 pp. Blaisdell. J. P., iuidj. F. Pechanec 1949. Effects of herbage remo\ul at various cLites on vigor of bluebunch \\heatgriiss ;ind ;uTo\\le;if b;i].samroot. Ecologv' .30: 29S-.305. 1992] Shakf-tailkd (Chouse Summkh Habitat 173 BvKHs (.'. H.. H. K. Si KiMiDHs I aiul P. H. Khmsm.w 1984. Clarification of a teclinicjiii' for aiiai\sis of utili- zatioii-a\aiIabilit\ data. Journal of Wildlife Manage- ment 48: 1050-1053. CiiiusTKNSON, C. D. 1970. Nesting ;uid brooding cluuac- teristics of Sluirp-tailed (Jroirse (Pcdioecctcs pluisianellus jainvsi Lincoln) in southwestern North Dakota. Unpublished thesis, Universits' of North Dakota, Grand Forks. 53 pp. CoN()\ KH \\: J. 1980. Practical nonpaianietric statistics. John \\'ile\ and Sons. New York. 493 pp. D.^LBKNMIRK, H. 1959. A canopv-coverage method of veg- etational analysis. Northwest Science 33: 43-64. DvKSTEHiiris, E. J. 1949. Condition and m;inagement of range land based on quantitative ecologv. Journal of R;uige Management 2: 104-115. E\.\NS. G. R., and E. W. Tisd.\le 1972. Ecological cluu-ac- teristics ot Aristida longiseta and Aoraptjron spimfniit in west-central Idaho. Ecolog\-53: 137-142. Fedkhai. Recister 1989. Endangered and Uneatened wildlife and plants; animal notice of review; proposed iiiles .54: 560. Giesen, K. M. 1987. Population characteristics and habitat use bv Columbiiui Sharp-tailed Grou.se in northwest Colorado. Feder;il Aid Project \V-37-R, Colorado Di\i- sion of Wildlife, Fort Collins. 28 pp. Gratson. M. W. 1983. Habitat, mobility and social patterns of Shaip-tailed Grouse in Wisconsin. Unpublished thesis, Uni\ersit\' of Wisconsin, Stevens Point. 91 pp. Griffith. B.,J. M.Scott, J. W. Carpenter. and C. Reed 1989. TriUiskxation as a species conservaticjn tool: status and strategv. Scienc-e 245: 477—480. Henderson, F. R., F'w. Brooks, R. E. Wood, and R. B. Dahlgren. 1967. Sexing of Prairie Grouse b\' crowii feather patterns. Journal of Wildlife Management 31: 764-769. Hill, M. O. 1973. Diversit)' and evenness: a unif\ing nota- tion and its consequences. Ecologv' .54: 427—4.32. lliRONAKA, M., M. A. FosBERc;, ancl A. W. Winward 1983. Sagebnjsh-grass habitat t\pes of southern Idaho. Universitv of Idaho, Forestrv. Wildlife, and Range E.xjx'riment Station Bulletin .35. Hitchcock, C. L., and A. Cronquist 1976. Flora of the Pacific Northwest. Universit\' of Washington Press, Seattle. 730 pp. HoLECHEK, J. L., R. D. Pieper, andC. H. Herbel 1989. Range niiinagement: principles and practices. Prentice Hall, Englewood (.'liffs. New Jerse\-, .501 pp, Jewett, S. G., W R Taylor. W. T' Shaw, and J. W. Aldrk.tl 19.53. Birds of Washington state. Universit)' of Wiishington Press, Seattle. 767 pp. Klott J. H., and F. G. Lindzey 1990. Brood habitats of sympatric Sage Grouse and (Columbian Shaq)-tailed Grouse in Wyoming. Journal of Wildlife Miuiagement .54: 84-88. LoNNKH T. N., and D. E. Burkhalter 1986. Users manual for the computer program TELDAY. Montana Depiirtinent of Fi.sh, Wildlife, tuid Parks, Bozem;ui. 15 pp. Marks J. S., and V. S. Marks 1987a. Habitat selection by Columbian Shaip-tailed Grouse in west-central Idaho. Bureau of Laiul Management Re^xjrt, Boise, Idaho. 115pp._ . 1987b. Influence of radio collars on snr\i\al of Sharp-tailed Grouse, journal of Wildlife M;uiageinent 51: 468^71. . 1988. Winter habitat use In (Columbian Shaip- tailed Carouse in western Idaho |ournal of Wildlife Management 52: 74.3-746. Miller. G. C, and W. D. Graul 1980. Status of Shaq> tailed Grouse in North America. Pages 18-28 in P. A. Vohs and F. L. Knopf, eds.. Proceedings of the Prairie Grou.se S\'mposinin, Okhilioma State University Still- water Moll R C. (). 1947. Table of e(]ui\ alent populations of North .American small mannnals. Americiui .Midland Natural- ist 37: 22;i-249. MoNSEN, S., and R. Stfxens, eds. In prep;iration. Rehabil- itation of western range and wildlands. US DA Forest Service General Technical Report. Interniountain Research Station, Ogden, Utah. Muecc;ler. W. F., tuid W. L. Stewart 1980. (irassland and shnibland habitat tvpes of western Mont;uia. USDA Forest Senice General Technical Report INT- 66. Ogden, Utah. Neu. C. W'., C. R. Byers, and J. M. Peek 1974. A tech- nique for anaKsis of utilization-axtiilabilitv data. Jour- nal of Wildlife Management 38: .541-.545. Nielsen, L. S., and C. A. Yde 1982. The effects of rest- rotation griizing on the distribution of Shaq)-tailed Grouse. Pages 147-165 in J. M. Peek and P D. Dalke, eds., Proceedings of the VV'ildlife-Livestock Relation- ships Symposium, Universitv of Idaho, Moscow. Oedekoven. O. O. 1985. Columbian Sh;ir]3-tailed Grouse population distribution and habitat use in south central WVoming. Unpublished thesis, Uni\ersit\"of W\oming, Liiramie. 58 pp. Pepper, G. W. 1972. The ecolog\ of Sharp-tailed Grouse during spring and summer in the aspen parkkmds of Saskatchewan. Wildlife Report 1. Saskatchewiui DepiU^tment of Natural Resources, Regina. R^.MHARTER, B. G. 1976. Habitat selection ;uid movements of Shaqi-tailed Carouse hens during the nesting and brood rearing periods in a fire maintained brush prai- rie. Unpublished dissertation, Uni\ersit%()f Minnesota, St. Paul. 78 pp. Sas Institute, Inc 1982. SAS user's guide: statistics. 1982 edition. SAS Institute, Inc., Car); North Carolina. .5.84 pp. Software Designs 1984. Gcoscan users manual. Mon- tana Department of Fish, Wildlife, and Parks, Boze- man. 22 pp. TiSDALE. E. W., and ,M. Hironaka 1981. The sagebnish- grass region: a review of the ecological literature. Uni- versity of Idaho, Forestn, Wildlife, and Riuige Experiment Station Bulletin .33. Wasser. C. H. 1982. Ecolog\- iuid culture of selected spe- cies useful in re\egetating disturbed lands in the West. USDI Fish and Wildlife Senic-e OBS-82/56. .•^47 pp. YocoM, C. F. 19.52. Clolumbian Shaip-tailed Grouse iPedi- oecetes pliasianvUus coliiinhianus) in the state of Wash- ington. American Midland Natiualist 48: 18.5-192. Z\R. J. H. 1974. Biostatistical ;xnalvsis. Prentice-HiJl, Inc.. Englewood C'liffs, New Jersev 620 pp. ZeI(;ler. D. L. 1979. Distribution ;uid status of the Colum- bian Shaqi-tailed (irouse in eastern Washington. W'ashington Dej)artment of Game, Completion Report Project W-7()-R- 18. 26 pp. Received 25 September 1991 Accepted 16 March 1992 Great Basin NatiinJist 52(2), pp. 174-178 CHARACTERISTICS OF SITES OCCUPIED BY SUBSPECIES OF ARTEMISIA TRIDENTATA IN THE PICEANCE BASIN, COLORADO Thomas R. Cottrell and Chiules D. Bonham" Kit/ words: Artemisia tridentata. Colorado, sagehnisli, clirointifoij^raplu/, factor analysis, sod. Artemisia tridentata, big sagebiiish, is the dominant plant species in the Piceance Basin of western Colorado and displays great morpho- logical variabilitv between sites. The existence of at least three subspecies is widely accepted (McArthur et al. 1981, 1988). These are A. tridentata spp. tridentata Beetle, A. tridentata spp. ivi/oming^ensi.s Beetle and Young, and A. tridentata spp. vaseyana Beetle. Despite extensive research in the Piceance Basin (Redente and Cook 1986), we have found only one study referring to intraspecific taxa of sagebrush (Ward et al. 1985). This work referred to subspecies tridentata but did not indicate where this taxon was found. Because the taxa are known to respond differentiiilly to soil and climate factors (Hironoka 1978, Sturges 1978) their existence in the basin should be recognized. The present study was designed to identify the subspecies o{ Artetnisia tridentata present in the Piceance Basin and to describe soil characteristics of sites occupied by sub- species. Study Site The Piceance Basin comprises about 3()()() km" in Garfield and Rio Blanco counties of northwest Colorado (Fig. 1). The cUmate of the Piceance Basin is semiarid and shows extreme variability in monthlv precipitation (Wymore 1974). Consecutive months often receive little precipitation. The mean annual precipitation for eight weather stations in the region for the period 1951-70 was 35.3 cm, with a 95% confi- dence intei-val of ±18.7 cm. About one-half of the total precipitation falls as snow. The average annual temperature ranges from 7 C at 1800 m to - 1 C at 2700 m. The strong influence of topography on tem- peratiu'e and precipitation results in a complex of habitats in the basin (Tiedeman and Terwilli- ger 1978). Generally, soil development is corre- lated to elevation. At higher elevations, except ridge tops, soils are dark brown, shallow mollisols. At mid-elevations, aridisols are common on deep loess. The lowest elevations are characterized by entisols developed on heavy clays and deep, sandy alluvial soils. Methods Six sites dominated by sagebrush were selected for this study (Table 1). These sites spanned the environmental extremes of sage- brush habitat in the Piceance Basin. Two sites were selected from each of three broad topo- graphic regions. High mounttiin sites were about 2000 ni; upland terraces and valley bottom sites were below 2000 m. Sagebrush subspecies were identified bv the combined information of three techniques and verified by A. H. Winward, regional ecologist for Range and Watershed Management, USFS Intermountain Region, Ogden, Utah. The first technique involved field identification using moqihological characteristics based on keys by A. H. Winward and Tisdale (1977). Leaf sam- ples were taken for the other two procedin-es. Two-dimensional chromatography, as described by Hanks et al. (1973), was done on persistent overwintering leaves from three plants at each site except site 5, where the moqihologiciil vari- abilit)' of the sagebnish plants was greater than at the other sites. At this site five plants were ^Department of Biology, Colorado State University, Fort C^ollins. Colorado 80523. Range Science Department, (Colorado State University, Fort Collins, Colorado 80.52,3. 174 1992] Notes 175 m. ''830 WYOMING PICEANCE BASIN C OLORADO NEW MEXICO 2130- 24 30- Meeker P'il e^^ 40°N / PICEANCE BASIN COLORADO SCALE IN MILES SCALE IN KILOMETERS CONTOUR INTERVAL 300m Fig. 1. The shulv iirea of the distribuHcMi ,A Anemisia trklcutata subspecies i„ northuest Colorado. tested by chromatography. Results were com- matelv IS other plants in the stucK- sites Leaves pared with representative chromatograms. The were crushed In hand and placed in glass con- hird procedure was a leaf extract in uater. This tainers for four hours. These were viewed under Uitter method was performed on all plants tested long-wave ultraviolet light and compared to by chromatography and on a total of approxi- descriptions by Stevens and McArthur (1974) 176 Great Basin Naturalist [Volume 52 Tabi.K 1. Location, elevation, ;uid sagebnisli subspecies of stutly sites. VAS — ssp. id.sci/ana: TRI — ssp. tridoitata: WTO = ssp. wuoimngensis. Selected soil characteristics are listed for ()-L5 cm and 16^30 cm soil samples for each site. L()cation Site Elev. ssp. Depth in cm % sand % silt pH C:aCO^ est. llji^h mountain I 2.365 VAS 0-15 54 26 6.9 low 1.5-30 52 26 6.8 low 2 2585 VAS 0-15 40 33 6.8 low 1.5-.30 36 33 6.5 low Viilley bottom 3 1987 TRI 0-15 74 13 8.2 med 1.5-.30 67 20 8.1 med 4 2057 TRI 0-15 56 30 8.1 med 1.5-.30 52 32 8.2 med Upland terrace 5 1920 WYO 0-15 46 27 8.2 med 15-30 51 27 8.3 med 6 2070 WTO 0-15 32 45 7.7 med 1.^.30 28 44 8.2 med In each site, soil samples were collected at two random locations from two depths, 0-15 cm and 16-30 cm. These were analyzed for pH, organic matter, electrical conductivity, esti- mated CaCOa, sand, silt, clay, K, Mn, Zn, Cu, P, and Fe. These data were used in a factor analysis as described by Affifi and Clark (1984). the factor scores for each site and depth were then graphed. This graph was used to inteqDret the axes that usually represent some environmental characteristic associated with plant species. Results Sites 1 and 2 were high mountain sites. Sage- brush plants averaged less than 50 cm in height. (Common associated plants were Liipimis .sp., ChnjsotJiamnus viscidiflonis, Eriopes of lakes and reservoirs that are important for migrating shorebirds, (2) to identih' habitat characteristics at these wetlands used b\ shorebirds, (3) to determine the inilu- ence of mudflat exposure and water le\el cliang(^s on shorc^bird use. Study Ahk.\s and Methods A total of 19 lakes and resenoirs were cen- sused at least once in 1989 (Table 1). Nine high-ele\'ation lakes were visited in the Saw- tooth Wilderness in earlv September 1976, and three high -elevation lakes in the Seafoam area of the Frank Church River of No Return Wil- derness in earlv .August 1990. Additional obser- vations from Lake Lowell were made in 1986, 1987, and 1990. All shorebirds were censused within 100 m of the shoreline in and out of the w ater at all sites; thus, evei-v 500 m of transect censused was equal to 0.1 km". We estimated birds per 500 m of shoreline for our densitv estimates. The Springfield area of American Falls Reservoir had over 15 km of mudflat exposed by drawdown during the study period and also included numerous seep areas awav from the main shoreline; because of this, it was not possible to make density- estimates from this site. Four of the lakes and reservoirs visited in 1989 had mudflat areas that were censused at least six times at roughly weekly inteivals from mid-Julv to earlv September, the time of peak shorebird abundance in Idaho (Tavlor et al. 1992). We used ANOVA and Newman-Keuls tests (Zar 1974) to compare differences in shorebird numbers at these four sites. Birds were censused bv walking from 10 to 1 00 m back from the shoreline and using binoculars and a 25X spotting scope. Care was taken not to dis- turb birds. If birds moved, their numbers were kept track of, or the entire coimt was restartc^d to avoid counting birds more than once. Results The natural lakes at high elevations we cen- sused in 1989 (Table 2) had onfy 0-2 Spotted Sandpipers (see Table 3 for cill scientific names). Only a single Spotted Sandpiper was found at nine high-elevation lakes visited in the Sawtooth Wilderness in September 1976. No shorebirds were found at three high-elevation lakes in the Seafoam area in early August 1990. At the Lowell, Walcott, American Falls, and Carey areas we found significant differences in the densities of total shorebirds (ANO\'A, F2(3) 26 = 88.76, P < .001). Lake Lowell had signifi- cantly the most shorebirds, American Falls had significantlv more than Carey Lake, but Carey Lake's higher mean was not significantlv more than Lake Walcott s (Newnian-Keuls, q = 29.89 to 7.47, for significant differences P < .05 or greater; (j = 2.04, P = :2 for Carey Lake-Lake Walcott). These differences in shorebird num- bers reflect the amount of mudflat available at the different sites; the larger the mudflats, the greater the number of shorebirds. The pattern of more shorebirds being attracted to larger mudflats is further supported In shorebird numbers at different Lowell sites Department of Biolopcal Sciences. Idaho State University, Pocatello. Idalio 83209 179 180 Great Basin Naturalist [Volume 52 TaBI.f: 1. Characteristics of hkilio lakes ;uicl reservoirs sur\'eyecl for shorehirds in 19S9. Transect Elevation length Name County (m) (m) Habitat Reservoirs and lakes with mudflats American Falls Power 1321 900 500 m mudflat Lowell C;inyon 757 4600 1200 m mudflat Walcott Minidoka 1279 1500 20 m mudflat Carey Blaine 1453 2200 200 m mudflat Little Camas Elmore 1502 800 120 m mudflat Dry Ciuiyon 818 15(X) 50 m mudflat/700 m grass Mackay Custer 1849 1400 200 m mudflat Palisades Bonneville 1708 1600 1000 m mudflat Reservoirs and lakes without mudflats Cascade ViJley 1472 2600 1-2 m sandy or muddy shore Wilson Jerome 1224 1800 dirt or grass shore Boulder Valley 2127 900 2 m mud or rocky shore Bnineaii Owyhee 763 23(:K) 1 m mud or sandy shore High-elevation lakes Alice Blaine 2622 1000 herb or rocky shore Toxaway Custer 2539 9(K) herb or rockv shore Edith Custer 2611 6(X) herb or rocky shore East Valley 2373 1100 herb or rocky shore West Valley 2361 900 herb or rocky shore North Valley 2367 7(X) herb or rocky shore Payette Valley 1522 700 herb or rocky shore responding to changes in mudflat conditions in 1989 (Fig. 1). In July Public Access No. 1 had verv' few shorebirds, and nearly all of its mudflats were submerged by water (Fig. lb). The New York Canal site was submerged at this time and had no birds (Fig. la). When the large mudflats of the New York Canal site became exposed in August, thousands of shorebirds appeared there (Fig. la). Numbers of shore- birds at some of the other sites declined (Fig. lb), which may have been due in part to birds shifting to the New York Canal site. The reflood- ing of Lowell in late September 1989 com- pletely eliminated shorebirds from census areas by 27 September (Fig. 1), although American Falls Reservoir had over 500 shorebirds at this time. On 27 September 1990, uith Lake Lowell very low due to dam reconstniction, there were extensive mudflats at the New York Canal site, and 926 individuals of 10 species of shorebirds were present. In earlv Julv 1986 there were hundreds of shorebirds on the exposed mudflats at Public Access No. 1, but in early July 1987, with high water flooding into riparian vegetation at this site, there were no shorebirds. The reservoirs we counted once or a few times in 1989 usually supported the pattern of total shorebird numbers declining with decreas- ing mudflat size, but there were some excep- tions (Table 2). Wilson, Boulder, and Cascade reservoirs all had zero or onh' a few meters of exposed shoreline, and thev had only 1 or 2 shorebirds. Mackay Reservoir had onlv 2 shore- birds on 3 July when no mudflats were exposed, but 351 two weeks later when there was 200 m of mudflat. The Drv^ and Little Camas reservoirs supported hundreds of shorebirds (Table 2), and these sites had mudflats of 50-120 m. How- ever, Bruneau had onlv 1-2 m of mud or sandy beach, and it had 79 individual shorebirds. An even stronger anomalv was Palisades, a reservoir which had exposed mudflats of about 1000 m and water drawdown continually exposing new areas, but practicallv no birds (Table 2). Black-bellied Plovers, Lesser Golden-Plo- vers, Sanderlings, Pectoral Sandpipers, and Stilt Sandpipers were found only on mudflats with >500 m of exposed mud (Table 3). Ten other shorebirds species were most abundant at sites with >500 m of exposed mudflat. Eight shore- bird species had similar-sized peaks at sites with >500 m or between 20 and 200 m of ex'posed mudflat. The onlv species with a maximmn peak on mudflats between 20 and 200 m was the uncommon Long-billed Curlew. No individual shorebird species had maximum numbers at 1992] Notes 181 Table 2. Total numher and, in parentheses, densit\ per 0.5 km of transect ol sliorehirds counted at lakes and reservoirs in Idaho in 1989. Count area Mean SD Range Springfield American Falls 9 9 Lowell 8 Wiilcott 9 Carey 6 Little Camas 4 Da' 4 Macka\- 2 Palisades 4 Cascade Boulder 2 1 Wilson Bnmeau Alice Payette Edith Toxawav West East North 2296 578.1 1698-3252 209 87.2 92-337 (105) (43.6) (46-168.5) 3061 1839.6 752^5739 (323) (230.6) (7^717) 54 40.6 17-153 (18) (13.4) (6-.50) 254 111.9 80-393 (58) (25.4) (1^89) 294 161.5 117^46 (184) (101.0) (7;3-279) 132 28 93-158 (44) (9.3) (31-53) 177 2^51 (62) (1-125) 18 23.6 0-70 (6) (8.3) (0-18) 0 1 (0.6) 0 79 (17) 1 (1) 0 0 1 (0.7) 0 0 0 sites with <5 m of mudflats or rocWlierh shore- lines. Discussion Tlie \irtiial absence of shorebirds from the 19 hi.5tK) in. Moderate mudflats include Carey, Little Camas, Di\' (in part), Mackay, and V\'alcott. and had water drawdouii exposing 20 2IKI ni ol mudflat. Muddy shores included Dry (in part), Bnmeau. Oiscade, Boulder, and Payette (in part), and tliese included small muddv shorelines or iiiudflais of .5 m widtli or less and also sandy or dirt shorelines. Rocky/herb shorelines included Alice. Dry(in])art), Kitst. F.ditli. North. Pavette l in parti, Toxawav, and Wil.son. 19921 Notes 183 shorebirds 1500 - Public #1 0 Public #2 /\ 1000 - Public #3 / \ B Q / 1 500 - \ j\l \ • ^ :^^^*=*-fcJl Q' ' T '^ T ■ -r ■ 1 ■ 1 ' 1 ■ 1 ' T '^P • isades Reservoir in tliis stiicK, indicates there are additional factors inflnencing shorebird use. This could include food abundance (Harrison 1982, Myers et al. 1987), which is important at American Falls Resenoir (Mihuc 1991), tradi- tional use (Myers et al. 1987), and in the case of Palisades Reservoir possible difficulty of shore- birds locating it because it is enclosed by high mountains in all directions (personal observa- tion). Steep-sided resenoirs, such as C. J. Strike, Hells Canyon (personal observation), and Lower Granite Creek (Monda and Reichel 1989) on the Snake River, and stretches of the Columbia River subject to water level fluctua- tions (Books 1985), supported few shorebirds even with water drawdown in summer and tail. The absence of shorebirds at Lake Lowell and Mackay Reservoir from sites when high water covered mudflats shows the importance of water drawdown exposing these areas during migration. At American Falls Resenoir we have previously found shorebird numbers to be cor- related with rate of drawdown (Tavlor et al., unpublished data). Water levels at reservoirs in this region are usually determined by irrigation, power generation, recreational activities such as boating, or waterfowl management. It is impor- tant that controllers of water levels at reservoirs and lakes (1) become aware of the potential or real use of shorebirds in their area and (2) manage water levels for shorebirds whenever feasible. Fig. 1. W'eeklv counts of the total number of shorebirds at four sites at Lake Lowell, Canvon Co., Idaho, in 1989. (A) New York Canal Mouth site, with both total number of shorebirds and the amount of mudflat exposed. (B) Open circle is Public Access No. 1 site; open triangle is Public Access No. 2 site; vertical line is Public Access No. 3. Stilt, Greater Yellowlegs, Short-billed Dow- itcher, Wilsons Phalarope, and Red-necked Phalarope, along with the Long-billed Curlew, all often feed in water. The two remaining spe- cies with similar-sized peaks between large and moderate mudflats, the Killdeer and Spotted Sandpiper, were the most widespread. This study indicates that most reservoirs and lakes in Idaho and the Intermountain West can provide habitat for shorebirds in fall migration if they have moderate to large mudflats that can be exposed by water drawdown during summer and fall. The absence of shorebirds at some reservoirs with large mudflats, in particular Pal- ACKNOWLEDCMENTS We would like to thank E. Stone, S. Bailey, S. Hart, and two anonvmous reviewers for their comments on earlier drafts of this paper This studv was funded in part by the Department of Biological Sciences, Idalio State Universit}'. Literature Cited BooK.s, G. G. 1985. Avian interactions with mid-Columbia River level fluctuations. Northwest Science 59: 304- 312. Bl KLF.ICH, T. D. 1972. Birdsof Idaho. The Caxton Printers, Ltd., CiJdwell, Idaho. 467 pp. CoLWELL, M. A., and L. W. Ohinc; 1988. Habitat use by breeding and migrating shorebirds in soudicentral Sas- katchewan. Wilson Bulletin 100: .554-566. H.MNLINE. J. L. 1974. The distribution, migration, and breeding of shorebirds in western Nevada. Unpub- lished master's thesis, Universit)' of Nevada, Reno. 84 pp. lt\ND, R. L. 19.32. Notes on the occurrence of water and shorebirds in the Lochsa region of Idaho. Condor 34: 23-25. 184 Great Basin Naturalist [Volume 52 H\RRisoN, B. A. 1982. Untviiig the enigma of" the Red Knot. Living Bird Quarterly 1: 4-7. MlHUC, J. 1991. An experimental study of tlie impact ot shorebird predators on benthic invertebrates in Amer- ican FiJls Reservoir, Idaho. Unpublished master's thesis, Idaho State University, Pocatello, 61 pp. MONDA, M. J., iuid J. D. Reichel 1989. Aviiui connnunitv changes following Lower Granite Dam construction on the Snake River, Washington. Northwest Science 63: 13-18. Myers. J. R, R. I. G. Morrison. R Z. Antus. B. A. Har- rington. T. E. LovEjOY, M. Sallaberry, S. E. Senner. and A. Tarak. 1987. Conservation strategy for migratorv shorebird species. American Scientist 75: 18-26^ RUNDLK VV. D., and L. H. Fredrickscjn 1981. Miuiaging seasonally flooded impoundments for migrant rails and shorebirds. Wildlife Societv Bulletin 9: 80-87, Senner, S. E., imd M. A. Howe 1984. Con.servation of Nearctic shorebirds. Behavior of Marine Animals 5: 379-421. Taylor, D. M., C. H. Trost. and B. Ja.mison 1992. Abun- dance iind phenology of migrating shorebirds in Idaho. Western Birds 23:49-78. Zar J. H. 1974. Biostatistical ;malvsis. Prentice-Hall, New Jersey. 620 pp. Received 15 September 1991 Accepted 1 May 1992 Great Basin Natuidist 52(2), pp. 185-188 DISPERSAL OF SQUARROSE KNAPWEED {CENTAUREA VIRGATA SSP SQUARROSA) CAPITULA BY SHEEP ON RANGELAND IN JUAB COUNT\', UTAH Cind\ Talbott Roc-he ', Ben F. Roche, Jr. , and G. Allen Rasniu.s.sen Key words: Centaurea \irgata ssp. s(|uarrosa, sciiiarrosc knapweed, weed dispersal. ranf^eUnid weeds, wool, sheep. Among Centaurea species naturalized in western North America, squarrose knapweed (Centaurea virgata Lam. ssp. sqiiarrosa Gugl.) has a unique dispersal mechanism. The seeds (achenes) of other CentourtY/ species (C. diffusa Lam., C. maculosa Lam., C. solstitialis L., C. jacea L. x C nigra L.) disperse either as indi- viduals with crop seed, vehicles, and gravel, or as branches or entire plants moved by wind or vehicles, or in hay. Squarrose knapweed involu- cral bracts recurve or spread outward with a short tenninal spine about 1-3 mm long. The entire head (capitulum) is deciduous via an abscisson laver at the base of the capitulum. Thus, the capitula of squarrose knapweed func- tion like burs clinging to passing animals as l)urdock {Arctium minus (Hill) Bemh.), cockle- bur {Xantliium strumarium L.), or buffalobur {Solanum rostratnm Dunal). Soon after the dis- covery of squarrose knapweed in California (1950) and in Utah (1954), its occurrence was linked to the practice of trailing rangeland sheep from one area to another (Bellue 1954, Tingey 1960). On Utah rangeland squarrose knapweed is more abundant along sheep trails and on bedgrounds than in other areas (H. Gates and T Roberts, personal communication). Wool is idealK suited to catching and holding the burlike capitula, but squarrose knapweed along trails and in sheep bedgrounds may have been carried by vehicles or other means and estab- lished in soil disturbed b\' sheep. The objective of this study was to determine if the distribution of squarrose knapweed in Utah is due to seed carried in the wool of rangeland sheep. Methods and Materials In mid-April 1990, sheep examined in this study were trailed from winter range west of Tintic Junction, Juab Comity, Utali, and sheared before being mo\'ed to spring range. We received permission from the owoiers to collect wool samples during shearing of a band that had wintered on rangeland known to have squarrose knapweed. We had predicted that sheep would pick up the "burs'" by lying on or brushing against knapweed plants growing on their bedgrounds. However, we saw no obvious knap- weed capitula in bellv wool or on the sides of sheep being sheared. One shearer pointed out several ewes with a profusion of kiiapweed capitula around their faces and on top of their heads (Fig. 1). We then collected samples of topknot wool (that shorn from the top of the head) from 458 randomly selected white ewes from a band of approximately 2500 ewes at the Jericho shearing station in Juab Count); Utah. Black ewes were not sampled. Samples from individual ewes, averaging 10 g, were kept sep- arate in small plastic bags. Squarrose knapweed capitula were sorted bv hand from each sample, and the number of achenes per capitulum was recorded. Filled achenes (hard, plump, dark tan or browni achenes) and light aclienes (.softer, flatter, pale tan or whitish achenes) were recorded separately. Presence or absence of insect o^AhiUropJiora ajfinis Frauenfeld and U. (juadrifasciata [Meigen]) in the knapweed capitula was noted. Achene viabilit)- was determined with germi- nation trials nm for 10 da\s at 20 C, 12 hours ^Department of Natural Resource Sciences. Washington State University. Pullman, Washington 99164-6410. "Present address: Department of Plant. Soil, and Entomological Sciences, University of Idaho, Moscow. Idaho 8.3843. ' Department of Range Science. Utah State University, Logan. Utah 84.322-5230. 185 186 Great Basin Naturalist [Volume 52 Fig. 1. Numerous squarrose knapweed capitula were caught as burs in the topknot wool of sheep that Iiad wintered where squarrose k-napweed occurred on rangekind in Juab Count\', Utah. T.^BLE 1. Proportion ol capituki containing 0-6 aclienes per capituhnn, comparing all capitula from iui intact plant with sheep-gathered capitula removed from topknot wool, in Juab Count)', Utah. Achenes/capituluni Intact pkuit '7c Extracted from wool 0 14 75 1 12 IS 2 19 6 3 35 1 4 17 trace 5 3 0 6 trace 0 light alternating with 12 hours dark. Seeds were placed in germination bo.xes on wetted blotter paper. Filled and light achenes were tested sep- arately. We germinat(Hl 30 filled achenes in four replications in each of two trials. Two trials of light achenes were run with 20 seeds in each of two replications. In August 19" Fig. 2. Squarrose knapweed phuits along the sheep trails west ot the Jericho she;iring station were grazed in mid-April 1990. A few capitula remain on the npper right side of the plant. heads would lead a casual obsener to couclude that the sheep carty more achenes than we found by dissecting the capitula. Among all ewes sampled, only 36% carried achenes in the sam- pled topknot wool. These seed-carriers aver- aged 4.5 filled achenes per 10 g wool. Those filled achenes averaged 69% germination. In addition to the filled achenes, 5% of the light achenes germinated. Light achenes composed only 23% of the total numbc^r of achenes. Discussion Sheep carried squarrose knapweed capitula but not as many achenes as the ninnber of capitula woidd indicate if the proportion were the same as that estimated in August. This find- ing could indicate one of two conditions: ( 1 ) the capitula were picked up in late winter or early spring, when only the lighter capitula remained on the plants, or (2) some achenes were lost from capitula lodged in the wool during late summer or fall. In late summer heavier capitula are more easil\- dislodged from plants than are the lighter capitula. Capitula do not open wideK' at maturity-; instead, achenes sift out throush a small opening created as the dried flowers fall from the capitulum. The proportion of empt)' capitula increases with time following maturity as plants are shaken b\- wind, animals, or \ehicles. Sheep acquired knapweed capitula in a manner different from what we had predicted. Although some capitula clung to sheep brushing against plants or King upon them, the numerous knapweed capitula in the wool aroiuid their faces suggest that ewes searched out squarrose knapweed as a food source. We observed that scjuarrose knapweed plants along the sheep trails had been grazed (Fig. 2). This relationship was nuitually beneficial for knapweed and sheep, providing propagule dispersal for the knapweed and nourishment for the sheep. Previousl) reported to be poor forage (Tingev 1960), squarrose knapweed rosette leaves may be an excellent source of protein in late winter and early spring. Nutrient content of spotted knapweed rosette leaves is comparable to native forage plants with 9-18% crude pro- tein (Kelsey and Mihalovich 1987). Similar values have been obtained for diffuse knapweed and yellow starthistle rosette leaves (Roche, unpublished data). In the stud\' area, Septem- ber 1989 through Mav 1990 was unusualK' dry (Utah State University' Tintic research site weather station, unpublished data), and the normal growth of cheatgrass {Bromus tectorum L.) was not present on the winter range. Squarrose knapweed, a deep-rooted perennial forb, was one of the few plants exhibiting new growth at the time sheep would normalK forage on cheatgrass. Although we found that sheep carr>- squarrc:>se knapweed seeds as they move across rangeland, they are by no means the only dis- persal mechanism for squarrose knapweed. Other animals, both domestic and wild, may carry knapweed seeds. In addition, these rangelands are hea\il\- used b\- off-road \ehicle recreationists. Mining traffic, railroad acti\it\'. and militar\' maneuxers are important in certain areas. Hunters, rockhounds, and other recreationists also frequent the area. Shearing limits the dispersion of scjuarrose knapweed b\- sheep. It is unlikeK that knapweed achenes remained on sheep after shearing. These ewes had not yet lambed, and so all sheep in this band left the knapweed-infested winter range shorn of seeds. Seeds in the wool are remox ed at the woolen mill, which has been one of the fates of squarrose knapweed seed for 188 Great Basin Naturalist [Volume 52 centuries, as evidenced by squarrose knapweed found at Juvenal Gate, a woolen mill in France where imported wool was washed for 200 years, beginning in 1686 (TheUung 1912). Acknowledgments This study was made possible by the cooper- ation of H. Gates and T. Roberts (Bureau of Land Management), S. Dewey (Utah State Uni- versity), and the ranchers who permitted us to sample wool during their shearing operation. J. Miller, Universit)' of Idaho, was consulted con- cerning vegetable matter in wool. E. Evans and D. Scamecchia reviewed the manuscript and provided valuable suggestions. The project was fimded in part by the Renewable Resources Extension Act through Washington State University Cooperative Extension. Literature Cited Bkllue, M. K. 1952. Virgate stiir thistle, Ccntaurca virgata vai". squarrosa (Willd.) Boiss. in California. California Dep;xrtnient of Agriculture BuOetin 41: 61-63. Kelsey, R. C, and R. D. Mhialovich. 1987. Nutrient composition of spotted knapweed {Centatirea maculosa). Journal of Range Management 40: 277- 281. Roche, C. T, and B. F. Roche, Jr 1989. Introductory- notes on squarrose knapweed (Centatirea virgata Lam. ssp. squarrosa Gugl.). Northwest Science 63: 246-2.52. Thellung, a. 1912. La flore adventice de MontpelLier. Memoires de la Societe Naturelles et Mathematiques de Cherbourg 38: 57-728. TiNGEY, D. C. 1960. Control of squarrose knapweed. Utixli State University Experiment Station Bulletin No. 432. 11 pp. Received 11 March 1991 Accepted 31 March 1992 Great Basin Natunilist 52(2). 1992. pp. 189-193 VEGETATION ASSOCIATED WITH TWO ALIEN PLANT SPECIES IN A FESCUE GRASSLAND IN GLACIER NATIONAL PARK, MONTANA R()l)in W. Tyser Ki'i/ icord.s: alini flora. CJacicr F20 m away from the ditch and is not part of the road-cut corridor. The remaining portion of the studv site is composed of a stand of natixe Festuca grasses and associated \egeta- tion in which inxasion by alien species has been minimal. Though no homesteading is known to ha\ e occurred in the .studv area before establish- ment of the park in 1910, this area was likel\ used as summer pasture for concession trail horses from approximately 1915 to 1940 (B. Fladmark, personal communication). The study area has not been used for stock grazing since that time. Othenvise, there is no indication that any of the areas sampled in the three stands have been subjected to anthropogenic disturbance Department of Biolog\ and MicTol)iolog\, I'niversitv of Wisconsin-La Oosse, La Crosse. Wisconsin 546()L 189 190 Great Basin Naturalist [Volume 52 since the park was established. In addition, no fires have been recorded in or near the study area since 1910. A cnptogani ground layer com- posed of small lichens and mosses covering undisturbed soil surfaces is commonly present. Qualitative observation suggests that mosses are the dominant element in this layer. Mean annual precipitation in the study area is ca 65 cm (Finklin 1986). In each stand, vegetation was sampled using 20 X 50-cm quadrat frames along two transects placed in representative areas. Within each quadrat, presence of all vascular species was determined, and the canopy cover of each vas- cular species and the surface cover of the cry|3- togamic ground crust were estimated to the nearest percentage. A stratified random sam- pling procedure was used in which quadrats were randomly placed along transect segments of fixed length. For the Centaurea stand, tran- sects were 20 m long, and one quadrat was randomly placed within each 2-m segment (N = 20 quadrats). For the Plilcmn and Festuca stands, transects were 100 m long, and one quadrat was randomly placed within each 5-m segment (N = 40 quadrats per stand). Five vegetation measures were calculated for each individual quadrat: (1) vascular species cover diversity using the Shannon -Wiener index (H' = -S Pi log p,), (2) vascular species richness, (3) cumulative canopy cover of native forb spe- cies, (4) cumulative canopy cover of native grass species, and (5) surface cryptogam cover. One- way ANOVAs were used to assess among-stand differences for each of these quadrat measures. With the exception of the diversity measures, data did not meet parametric assumptions (normal distributions, homogeneous variances) and could not be transformed using standard logarithmic, arcsine, or square root transforma- tions. Therefore, data were analyzed by the Kruskal-Wallis nonparametric one-way ANOVA procedure as described by Conover and Iman (1983). The Tukey multiple compari- son procedure, applicable to both parametric and nonparametric ANOVAs (Conover and Iman 1981), was used to make pair-wise among- stand comparisons. Species nomenclature fol- lows that of Hitchcock and C^rontjuist (1973). Results and Discussion Prominent graminoid and forb species in the Festuca stand included Achillea millefolium. Carex spp., Festuca idahoensis, F. scabrella, Gaillardia aristata, and Lupinus sericeus (Table 1). Species composition of this stand was similar to prairie communities described elsewhere in the Pacific Northwest, e.g., the Festuca scabrella/F. idahoensis association of western Montana (Mueggler and Stewart 1980), the Festuca/Danthonia prairie of Alberta (Stringer 1973), and the Washington Palouse prairie (Daubenmire 1970). Estimated surface cover of the cryjDtogam layer in this stand was relatively high, characteristic of western bunchgrass prai- ries (Daubenmire 1970, Mack and Thompson 1982). Three alien species were sampled within the Festuca stand, though total cover of these species was <1.0%. Significant among-stand variation occurred for all community measures (Table 2). Each of these measures was lowest in the Centaurea stand. Canopy cover of native forbs and crypto- gam ground cover in this stand were particularly low, only ca 18% and 4%, respectively, of the corresponding Festuca stand measures. Thus, effects of the Centaurea macidosa invasion on the native flora in the study site appear to be relatively severe. The impact of this species is even more impressive considering its relatively recent entry into the park. All but one of the Phleum stand measures were significantly lower than those of the Festuca stand (Table 2). Canopy cover by native graminoids in the Phleum stand was reduced to about 50% of its level in the Festuca stand. However, forb cover differences between these two stands were not statisticiilly significant (Table 2). Three species {Achillea millefolium, Agoseris glauca, and Lupinus sericeus) were among the four forb species with highest canopy cover in each stand, suggesting that the forb components of these two stands were relatively similar. These observations suggest that Phleum invasion has affected natixe graminoids more than native forbs. It should also be noted that while mean quadrat richness was lower in the Phleum stand (Table 2), eight more species were recorded in this stand than in the Festuca stand (N = 59 vs. N = 51; see Table 1). Thus, different Phleum vs. Festuca richness patterns may occur if comparisons are derived from sampling units larger than the 0.1-m~ quadrats used in this study. Cryptogam cover in the Phleum stand was approximately 50% lower than in the Festuca stand (Table 2). Mack and Thompson (1982) 1992] Notes 191 Table 1. Canopv cover (%) estimates of six^cies within the Fcstuca, Phlcitin, and Ccnidurcd stands. ° = iJien sjieeies. Species Festuca Phleuni Centaurea GlUMINOIDS Agropijron caninum 0.4 0.6 Agroptjwn spicatum 0.3 0.3 Carex spp. 12.3 5.6 9.3 Danthonia intcmivdia 4.2 0.9 Fcstuca iclaliocnsi.s 9.2 4.3 0.2 Fcstuca saibrclla 7.1 4.1 2.1 Hclictotrichon hookcri 0.9 <0.1 Kitclcria crlstata 1.4 0.4 <0.1 Flileum pratense' 0.2 38.4 0.7 Fodjuitcifolui <0.1 Poa pratcnsis' <0.1 0.9 1.0 Stipa occidentalis 3.7 2.1 Stipa rirhnrrlxonii 0.1 0.8 FOKBS Achillea millefoliuiu 11.7 8.6 0.8 Agoscri.'i glaiica 4.0 4.3 Allium cenmiim 0.1 <0.1 Atnehmchicr alnifolid 0.3 0.9 0.5 And rosace septenthoiidli.s 1.0 0.3 Anemone midtifida 1.4 1.0 <0.1 Antennaha inicroplujlld O.S 0.3 1.7 Arahis <^lahra <0.1 Arahis nuttallii 0.2 0.1 <0.1 Arctostaplujlos u vd-tt rsi 0.4 0.2 Aster laevis 1.8 0.9 Berheris repens 0.1 0.6 0.3 Campanula rotundifolid 0.5 1.0 <0.1 Castilleja aisickii 0.3 <().! Centaurea nmculosa' 62.0 Cerastiu m arven.se 4.0 3.1 0.7 Colloniia linearis <0. 1 Comandra nmtjeltata 0.5 0.3 Species Festuca Phleum Centaurea Epilohium angustifoliu m 0.5 F,rigeron suhtrinervi.s 1.5 Erysimum inconspicuum 0.3 Fru'^a ri a v i r^i niana <0.1 0.7 Gaillardia aristata 1.9 0.6 <0.1 Galium horeale 0.6 1.8 0.2 Gentiana amarella 1.3 0.7 Geran iu m viscosissimum <0.1 1.2 Hedijsanun horeale 0.5 Heuehera cijlindhca 0.1 0.2 0.2 Hieracium umhellatum 0.2 Jiinctts haltieus 1.0 Latlujriis oehroleucus 0.2 Lithospermu m niderale 1.9 3.9 0.7 Lonmtium tritematum 1.0 2.4 0.3 Ltipinus serieeus 5.6 6.0 <0.1 Monarda fistulosa 0.6 Orthocarpus tenuifolius 1.2 <().! Oxijt n )p is cam pest ris 2.8 0.9 Oxtjtropi.s splendens 0.3 Penstenum confertus 0.8 1.9 0.7 Potentilla arguta <0.1 1.1 Potentilla is^racilis <0.1 0.4 0.3 Potentilla hippiana 0.5 Pninus virSER, R. W'., and C. H. KEn 1988. Spotted knapweed in natural area fescue gr;isslands: an ecological assess- ment. Northwest Science 62: 151-160. 'HsF.R. R. VV., iind C. A. WoRLF.V 1992. Alien flora in grass- lands adjacent to road and trail corridors in Glacier National Park, Montana (U.S.A.). Conservation Biol- ogy. In press. Watson. A. K., and A. J. Renney 1974. The biolog\- of Canadian weeds. 6. Centaurea diffusa and C. nmailosa. C inadiiin Journal of Plant Science .54: 687-701. Weaner. T, and B. Wbons 1985. The exotic flora of Glacier Nation;U Ptuk: apreliniiniin atlas. MSU Biology Report 37. Montana State Uiii\ersit\-. Bozeiuan. 49 pp. . 1986. The exotic flora of Grand Teton National Park: an environmental atlas. MSU Report 38. Mon- tana State University, Bozeman. 48 pp. WiL.soN. S. D. 1989. The suppression of native prairie by alien species introduced for revegetati(jn. Landscape and Urb;ui Phuming 17: 11.3-119. YoLNc;. J. A., R. A. E\a\s. and J. Major. 1972. Alien plants in the Great Basin. Journal of Range Management 2.5: 194-201. Received 26 April 1991 Accepted 16 April 1992 INFORMATION FOR AUTHORS The Great Basin Naturalist welcomes previously unpublished manuscripts pertaining to the biologi- cal natural history of western North America. Pref- erence will be given to concise manuscripts of up to 12,000 words. SUBMIT MANUSCRIPTS to James R. Barnes, Editor, Great Basin Naturalist, 290 MLBM, Brigham Young University, Provo, Utah 84602. A cover letter accompanying the manuscript must include phone number(s) of the author submitting the manuscript; it must also provide information de- scribing the extent to which data, text, or illustra- tions have been used in other papers or books that are published, in press, submitted, or soon to be submitted elsewhere. Authors should adhere to the following guidelines; manuscripts not so pre- pared may be returned for revision. MANUSCRIPT PREPARATION. Consult Vol. 51, No. 2 of this journal for specific instructions on style and format. These instructions. 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White, eds.. The ecology of natural disturbance and patch dy- namics. Academic Press, New York. Coulson, R. N., and J. A. Witter. 1984, Forest entomology: ecolog>' and management. John Wiley and Sons, Inc., New York. 669 pp. TABLES are double spaced on separate sheets and designed to fit the width of either a single column or a page. Use lowercase letters to indicate foot- notes. PHOTOCOPIES OF FIGURES are sul)mitted initially with the manuscript; editors may suggest changes. Lettering on figures should be large enough to withstand reduction to one- or two-column width. Originals must be no larger than 22 x 28 cm. NOTES. If the manuscript would be more appro- priate as a short communication or note, follow the above instructions but do not include an abstract. A CHARGE of $45 per page is made for articles published; the rate for subscribers will be $40 per page. However, manuscripts with complex tables and/or nimierous half-tones will be assessed an additional charge. Reprints may be purchased at the time of publication (an order form is sent with the proofs). FINAL CHECK: • Cover letter explains any duplication of infor- mation and provides phone number(s) • 3 copies of the manuscript and WordPerfect disk • Conformity with instructions • Photocopies of illustrations (ISSN 0017-3614) GREAT BASIN NATURALIST voi 52 no 2 June 1992 CONTENTS Articles Red Butte Canyon Research Natural Area: history, flora, geology, climate, and ecology James R. Ehleringer, Lois A. Arnow, Ted Arnow, Irving R. McNulty, and Norman C. Negus 95 Influences of sex and weather on migration of mule deer in California Thomas E. Kucera 1 22 Diatom flora of Beaver Dam Creek, Washington County, Utah, USA Kurtis H. Yearsley, Samuel R. Rushforth, and Jeffrey R. Johansen 131 Stratification of habitats for identifying habitat selection by Merriam's Turkeys Mark A. Rumble and Stanley H. Anderson 139 Pollinator preferences for yellow, orange, and red flowers of Mimulus verbenaceus and M. cardinalis Paul K. Vickery, Jr. 145 Soil loosening processes following the abandonment of two arid western Nev- ada townsites Paul A. Knapp 149 Biochemical differentiation in the Idaho ground squirrel, Spennophilus brun- neus (Rodentia: Scuridae) Ayesha E. Gill and Eric Yensen 155 New genus, Aplanusiella, and two new species of leafhoppers from south- western United States (Homoptera; Cicadellidae: Deltocephalinae) M. W. Nielson and B. A. Haws 160 Summer habitat use by Columbian Sharp-tailed Grouse in western Idaho . . . Victoria Ann Saab and Jeffrey Shaw Marks 166 Notes Characteristics of sites occupied by subspecies of Artemisia tridentata in the Piceance Basin, Colorado . . Thomas R. Cottrell and Charles D. Bonham 1 74 Use of lakes and reservoirs by migrating shorebirds in Idaho Daniel M. Taylor and Charles H. Trost 1 79 Dispersal of squarrose knapweed {Centaurea virgata ssp. squarrosa) capitula by sheep on rangeland in Juab County, Utah Cindy Talbott Roche, Ben E Roche, Jr., and G. Allen Rasmussen 185 Vegetation associated with two alien plant species in a fescue grassland in Gla- cier National Park, Montana Robin W. Tyser 189 H E MCZ LiijRARY V mo HARVARD UNIVhHSlTY GREAT BASIN MURAUST VOLUME 52 NO 3 - SEPTEMBER 1992 BRIGHAM YOUNG UNIVERSITY GREAT BASIN NATURALIST Editor James R. Barnes 290 MLBM Brigham Young UniversiU' Provo, Utah 84602 Associate Editors Michael A. Bovvers Blandy Experimental Fann, University of Virginia, Box 175, Boyce, Virginia 22620 J. R. Callxhan Museum of Southwestern Biolog)', Universit)' of New Mexieo, Albuquerque, New Mexico Mailing address: Box 3140, Hemet, California 92546 Jeanne C. Chambers USDA Forest Ser\ice Research, University of Ne\ada-Reno, 920 Valley Road, Reno, Nevada 89512 Jeffre\' R. Johansen Depiirtment of Biology, John Carroll University, Universit)' Heights, Ohio 44118 Paul C. Marsh Center for En\ironmental Studies, Arizona State University; Tempe, Arizona 85287 Brian A. Maurer Department of Zoolog); Brigham Young Uni\ersity, Provo, Utah 84602 JiMMIE R. PaRRISH BIO-WEST, Inc., 1063 West 1400 North, Logan, Utah 84321 Paul T. Tueller Department of Range, Wildlife, and Forestry, University of Nevada-Reno, 1000 Valley Road, Reno, Nevada 89512 Robert C. Whitmore Division of Forestry', Box 6125, West \'irginia Uni- versits', Morgiuitowai, West Virginia 26506-6125 Editorial Board. Richard \V. Bauniann, Ch;xirman, Zoolog)'; H. Duane Sniitli, Zoolog); Cla\ton M. White, Zoologv; Jerran T. Flinders, Botany and Range Science; William Hess, Botany anc{ Range Science. AJl are at Brigham Young University. Ex Officio Echtorial Board members include Clayton S. Huber, Dean, College of BiologiccJ and Agricultural Sciences; Norman A. Darais, Director, University Publications; James R. Banies, Editor, Great Basin Naturalist. The Great Basin Naturalist, founded in 1939, is published quarterl\- b\ Brigham Young Uni\ersit\'. Unpubhshed manuscripts that further our biological understancling of the Creat Basin and surrounding areas in western North America are accepted for publication. Subscriptions. Annual subscriptions to the Great Basin Naturalist for 1992 are $25 for indixidual subscribers, $15 lor student and emeritus subscriptions, and $40 for institutions (outside the United States, $30, $20, and $45, respectively). The price of single issues is $12. All back issues are in print and available for sale. All matters pertaining to subscriptions, back issues, or otlier business should be directed to the Editor, Great Basin Naturalist, 290 MLBM, Brigham Young University, Provo, UT 84602. Scholarly Exchanges. Libraries or other organizations interested in obtaining die Great Basin Naturalist through a continuing exchange of scliolarly publications should contact the Exchange Librarian, Harold B. L(^e Librar\', Brigham Young Universitv; Provo, UT 84602. Editorial Production Staff JoAnne Abel Technical Echtor Jan Spencer Assistant to the Editor Natalie Miles Procluction Assistant Copyright © 1992 b\ Brigluuii Young University Official publication date: 18 December 1992 ISSN 0017-3614 12-92 750 2473 The Great Basin Naturalist Plblishkd atPhono, Utah, by Bricham Young Um\ersi'it ISSN 0017-3614 Volume 52 September 1992 No. 3 Great Basin Naturalist 52(3), pp. 195-215 PLANT ADAPTATION IN THE GREAT BASIN AND COLORADO PLATEAU Jonathan P. Comstock antl James R. Elileringer Al5STlU(X — Adapti\e features of plants of tlie Great Basin are reviewed. The combination of cold winters and an arid to semiarid precipitation regime results in the distinguishing features of the vegetation in the Great B;isin and Golorado Plateau. The priniaiy effects of these climatic features luise from how the\ structure the hvdrologic regime. Water is die most limiting factor to plant growth, and water is most reliabK axailahle in the earl\- spring after winter recharge of soil moisture. This factor determines main characteristics of root moipholog\, growth phenolog\- of roots and slKX)ts, and photos\ndietic physiolog): Since winters are hpicallv cold enough to suppress growth, and drought limits growth during the summer, the cool temperatures characteristic of the peak growing .season are the second most importiuit climatic factor influencing plant habit luid perform;uice. The combination of several distinct stress periods, including low-temperature stress in winter and spring and high-temperature stress combined with drought in summer, appears to have limited plant habit to a greater degree thiui found in the warm de.serts to the south. Nonetheless, cool growing conditions and a more reliable spring growing season result in higher water-u.se eiiiciencv and productiv ih" in the vegetation of the cold de.sert than in warm deserts with equiv;ilent total rainfall amounts. Edapliic factors are also importimt in structuring communities in these regions, and halophvtic connnunities dominate main landscapes. These haloph\-tic communities of the cold desert share more sj^ecies in common with warm deserts than do the nonsdine communities. The Golorado Plateau differs from the Great Basin in having greater amounts of smniner rainfall, in some regions less predictable riiinfall, sandier soils, and streams which drain into river .systems rather than closed basins and salt plavas. One result ofthe.se climatic and edapliic differences is a more important summer grov\ing seasf)n on the (Colorado j'lati'au and a sonu-wliat l^eno 1340 1S2 61 24 15 9.5 3.3 8.4 18.0 3 Elko 1547 230 52 29 19 7.6 0.1 7.1 17.5 4 Snowxille 1390 300 43 33 24 7.4 0.7 6.2 18.4 Southern 5 Sarcobatus 1225 85 45 22 33 13.5 6.4 12.5 23.1 Great Basin rs C;iliente 1342 226 47 24 29 11.7 4.1 11.2 21.5 ' Fillmore 1573 369 44 34 •1-1 11.0 3.0 10.0 21.7 Moja\e Desfc 'rt S Trona 517 102 70 19 11 19.0 11.3 18.4 29.0 9 Bea\erdam 570 169 50 23 28 18.3 11.0 16.9 28.6 Colorado 10 Hanksxille 1313 132 36 19 45 11.4 2.1 11.5 22.8 Plateau 11 Clrantl Junction 147S 211 39 25 36 11.3 2.4 10.9 22.9 12 Blanding 1841 336 48 19 .33 9.7 2.1 8.7 19.9 13 TnbaCit\' 1504 157 38 21 41 12.6 4.8 12.0 22.8 14 (]haco Canvon 1S67 220 35 20 45 10.3 2.6 9.4 20.6 of the Colorado Plateau, which is thought to be a critical feature ensiuins soil moisture recharge and a reliable spring growing season (West 1983, CakKvell 1985, Dobrowolski et al. 1990). During the winter period, precipitation is gen- eralK' in excess of potential exaporation, but low temperatures do not permit gro\\1:h or photo- sxnthesis, and exposed plants may experience shoot desiccation due to dry winds and frozen soils (Nelson and Tienian 1983). Strong winds can also cau.se major redistributions of the snow- pack, sometimes rexersing the expected increase in [)recipitation with ele\ation and having important consecjuences to plant distri- butions (Branson et al. 1976, Sturges 1977, W'e.st and Caldwell 1983). The important growing season is the cool spring when the soil profile is recharged from winter precipitation; growth is usualK' curtailed b\- dning soils coupled with high temperatures in earl\- or mid-smnmer. A clear pictiu-e o( this climatic regime is essential to an\- chscussiou of plant adaiitations in the region. A second major feature affecting plant per- formance is the prevalence of saline soils caused l)\' the C()ml)ination of low precipitation and the internal drainage txpical of the Great Basin. In this paper we address the salient morphological, physiological, and phenological specializations of nati\ e plant species as the\' relate to siua i\al and growth tmder the constraints of these potentialK stressful limitations. We emphasize (1) edaphic factors, particularK soil salinit\ and texture, and (2) the climatic regime ensuring a fairlv dependable, deep spring recharge of soil moisture despite the overall ariditv; as factors molding plant adaptations and producing the uni(jue aspects of the regional plants and vege- tation. The majoritv of the Great Basin lies at moderatelv high elevations (4000 ft and aboxe), and it is occupied bv cold desert plant comnm- nities. Reference to "the Great Basin" and its environment in this paper will refer to this high- {^]e\ation region as distinct from that corner of the Mojave Desert that occupies the southwest- em corner of the Cireat l^asin geographic unit (Fig. 1 ). Our emphasis will be placed on these cold desert shnib communities in both the Great Basin and the Colorado Plateau ranging from the topographic low points of the saline plavas or cauNon bottoms up to the pinvon-juni- per woodland. The lower-elevation, warmer. 19921 Plant Adaptation 197 Great Basin Mojave Colorado Plateau Fig. 1. Distribution of the major desert vegetation zones ill tlie Great Bitsin and Colorado Plateau. Numbers indicate l(K'atioiis of climate stations for which data are presented in Table 1. Most of the Mojave Desert indicated is geologically part of the Great Basin, but, due to its lower elevation and warmer temperatures, it is climaticallv distinct from the rest of the region. antl drier Mojax'e De.sert portion of the Cjreat Basin will he considered primariK as a point of e()inj)arison, and for more tlioronii;h coxerage of that region we recommend the reviews h\ Ehleringer (1985), MacMahon (1988), and Smith and Nowak (1990). For the higher mon- tane and alpine zones of the desert mountain ranges, the reader is referred to rexiews l)\ \'asek and Thome (1977) and Smith and Knapp ( 1990). We are indebted in onr own c()\erag(^ of the cold desert to other rec-ent rexic^ws. includ- ing Caldwell (1974, 19S5). West (19SS). Dobrowolski et al. (1990), and Smith and Nowak (1990). The Great Basin and the Colorado Plateau share important climatic features such as overall ariditv; frequent summer droughts, and conti- nental winters; yet the\^ differ in other ecjualK important features. Temperatures on the Colo- rado Plateau are similar to ecjuixalent elexatioiis in the southern (Ircat liasin. hut suiiiiiici' pre- cipitation is suhstantially greater on the Colo- rado I'lateau (Tahk" \). Soils and drainage patterns also differ in crucial wa\s. The high- lands of the Colorado Plateau generally drain into the Colorado Hixer sv'stem. In manv areas extensive exposure of marine shales from the Chinl(\ \hmcos, and Morrison Brnshv-Basin formations wc^ithcr into soils that restrict plant diversitv and total cover due to high concentra- tions of NaSOa, and the formation of clavs that do not allow water infiltration (Potter et al. 1985). In other areas massive sandstone out- crops often dominate the landscape. Shrubs and trees mav root through ven shallow rock"v soils into natural joints and cracks in tlie sub.stratum. Deeper soils are generallv aeolian deposits forniinti sands or sandv loams. In contrast, high elevations of the Cireat Basin drain into closed \alleys and evaporative sinks. This results in greater average salinitA' in the lowland soils of the Great Basin, with NaCd being the most common salt (Flovxers 1934 ). and a more exten- sive development of haU)ph\ tic or salt-tolerant vegetation. Soils tend to be deep, especialK at lower elevations, and van' in texture from clav to sandv loams. Summer-active species with different photosvnithetic pathwavs, such as C4 grasses and CAM succulents, are poorlv repre- sented in nuich of the Crreat Basin, but the combination of increased summer rain, sandier soils, and milder winters at the lower elevations of the Colorado Plateau has resulted in a greater expression of phenological diversit\. The interactions of edaphic factors and cli- mate are complex and often subtle in their effects on plant performance. Furthermore, [)Iant distributions are rarelv determined bv a single factor throughout th(ir geographic range. e\en though a single factor mav appear to con- trol distribution in the context of a local ecosvs- tcMii. Species-spcxific characteristics generally do not inqxirt a narrow re(|uirement for a spe- cific environment, but rather a unique set of "ranges of tolerance" to a large arrav of enxiron- mental j)arameters. In different enviromncntal contexts, different tolerances mav be more lim- iting, both abiotic and biotic interactions may be altered, and the same set of species may .sort out in different spacial ])attenis. A further conse- (juence of this is that a local combination of species, whicli we might refer to as a Great Basin plant communitv. represents a region of oxerlap in the geograpln'calK more extensive 198 Great Basin Naturalist [N'oluiiie 52 and treiieralK miicjue tlistrihutioiis ot each coni- ponenf species. In fact, the distributions of spe- cies commonly associated in the same Great Basin connnunitv' may be strongly contrasting outside the Great Basin. This is an essential point in attempting to discuss plant adaptations with the implication oi cause and effect, because few species discussed will have a strict and exclusixe relationship with the environment of interest. Unless we can show local, ecot\pic differentiation in the traits discussed, we need to take a broad view of the relationship between environment and plant characters. In a few instances, a small number of edaphic factors and plant characters, such as tolerance of veiy high salinity in soil wdth shallow groundwater, seem to be of overriding importance. In most cases we need to ask, what are the common elements of climate over the diverse ranges of all these spe- cies? One such common element, which will be emphasized throughout this re\iew, is the importance of reliable winter recharge of soil moisture in an arid to semiarid climate. B\- iden- tifying such common elements and focusing on them, we do not fully describe the autecologv of an\' species, but we attempt a cogent treatment of plant adaptations to the Great Basin environ- ment, and an explanation of the unicjue features of its plant connnunities. Climate, Edaphic Factors, and Plant Distribution Patterns Typical zonation patterns observed in spe- cies distributions around playas (the saline flats at the bottom of closed-drainage basins) are quite dramatic, refl(^cting an o\ erriding effect of salinit)' on plant distribution in the Cireat Basin. Moving out from the basin center is a gradient of decreasing soil salinity often correlated with progressively coarser-textured soils. Along this gradient there are conspicuous species replace- ments, often resulting in concentric zones of contrasting vegetation (Flowers 1934, Vest 1962). In the lowest topographic zone, saline groundwater may be very neav the surface. Soils are ven' saline, fine textured, and subject to occasional flooding and anoxic conditions, in this enxiromnent the combination of available moisture with other poteutiallv stressful soil characteristics seems to be more important than climatic factors of temperatiu'e or seasonal rain- fall patterns. Speci(>s found here, such as desert saltgrass {Distichlis spic Cyreat Basin conu^ in contact with the lower-elevation, generallv drier, and warmer Mojave Desert region, comminn'ties ck)minated by creosote (Larrca tridfufafa) replace sagebrush commu- nities on nonsaline slopes and bajadas. 19921 Plant Adaitxtion 199 Shadscak' can ht' toiiiul liotli on saline soils at \en low t'k'\ ations in tlu^ Mojaw and as a tran- sitional band at liigli ekn ations l)et\\een creo- sote and sagebmsh. Elements of the cold desert shnib conimnnities, adapted to continental win- ter's and a cool s[)ring growing season, can be tonnd throughout the winter-rain-doniinated \h)ja\"e Desert region as a high-elexation band on arid mountain ranges. They also extend to the southeast at high ele\ations into the strongK- bimodal precipitation regime of the Colorado i'latean, and northward at low elexations into Idaho. Washington, andexen British (-oluinbia. Nhning up from bajadas of the southern warm deserts, there appears to be no suitable combi- nation of temperature and precipitation at an\' elevation to support floristic elements of the cold desert. As precipitation increases with alti- tude, zones with equivalent total precipitation do not \et ha\e cold winters and are occupied In warm desert shnib connnunities grading into chaparral composed of unrelated ta.xa. Higher ele\ ations with cold winters have sufficient pre- cipitation to support forests. Other elements coimnon in shadscale and mixed-shrub connnu- nities of the Great Basin, such as winterfat and budsage (Ai-tcmisia spiiiosa), are often found outside the Great Basin in cold-winter but largel\- summer-rainfall grasslands. f^rom these patterns of communitv- distribu- tion within the Great Basin and Colorado Pla- teau, and also from a consideration of the more extensive ranges and affinities of the component species, we can isolate a few ke\- features of the environment that are largely responsible for the unique plant features seen in the Great Basin. The most obvious features are related to the patterns of soil salinitv and texture generated bv the (Aerall ariditv combined with either internal drainasie basins or tlie in situ weathering of specific rock tvpes. The most important climatic variables are slightlv more subtle. There is cknulv not a requirement for exclusivelv winter rainfall, but there is a re(|uirement for at least a substantial portion ol the annual rainfall to come dniing a continental winter This permits v\inter (iccitninlatioit of precipitation iod 'greater depth in the soil profile than w ill occur in response to less predictable sunnner replenishment of dning soil moisture reserves. Unck'r an overall arid climate, winter n^charge maintains a pre- ilictablv favorable and ck)minant spring growing season even in manv areas of strongly bimodal rainfiill. Most of the phvsiological. moqihologi- cal. and plieiiological traits lonnd in llie (k)mi- nant shrubs rell(^ct the [)riman importance of such a cool spring growing .season. PlI()T(lSY\'THKSIS Piiotosyxtiiktk; I'ATIIWAVS. — The pro- cess of photosvnthesis in plants relies on the acquisition of CO2 from the atmo.sphere, which, when coupled with solar energ\', is transformed into organic molecules to make sugars and pro- vide for plant growth. In moist climates plant communities often achieve clo.sed canopies and 1(){)% cover of the ground surface. Under these conditions competition for light may be among the most important plant-plant interactions. In the deserts total plant cover is much less than 100%, and in the Great Basin closer to 259f. Photosviithesisisnotgreatlvlimitcxlbv available light, but rather bv water, mineral nutrients needed to .synthesize enzAines and maintain metabolism, and maximum canopv leaf-area development. Three biochemical pathwavs of photosvii- thesis have been described in plants that differ in the first chemical reactions associated with the capture of CO2 from the atmosphere. The most common and most fundamental of these pathways is referred to as the C3 pathway because the first product of photosynthesis is a 3-carbou molecule. The other two pathways, C4 and CAM, are basically modifications of the primaiy C3 pathway (Osmond et al. 1982). The C4 pathwav (first product is a 4-carbon mole- cule) is a morphological and biochemical arrangement that overcomes photorespiration, a process that results in reduced photosviithetic rates in C3 plants. The C.i pathway can confer a much higher temperature optimum for photo- .synthesis and a greater water-use efficiency. As water-use efficiencv is the ratio of photosvn- thetic carbon gain to transpirational water loss, C4 plants have a metabolic advantage in hot, dn^ environments w4ien soil moisture is available. In grasslands C4 grasses become dominant at low elevations and low latitudes where animal tem- ]x^ratur(\s are warmest. In interpreting })lant distribution in deserts, the .seasonal pattern of rainfall usuallv restricts the periods of plant growth, and the temperature during the rainy season is thus more important than m(\ui annual temperature. The C4 pathwav is ofti'u associated with smnmei-active species and also with plants of saline soils. While C3 grasses pre(k)minate in 200 Great Basin Naturalist [\'olunie 52 most of the Cireat Basin, C4 grasses beeonie iiicreasinglv important as summer rain increases to the south, and especiaHv on the Colorado Plateau. Halophvtic plants are often C4, such as saltbush iAfrij)Icx spp.) and saltgrass (Disticlilis spp.), and tliis mav gixe the plants a competitixe advantage from increased water-use efficienc\- on saline soils. The third photo.sMithetic pathway is CAM photosMithesis (Crassulacean Acid Metabolism). CAM plants open their stomata at night, capture COo and store it as malate in the cell \acuole, and keep theii stomata closed dining the dav (Osmond et al. 1982). The CO2 is then released from the vacuole and used for photos)aithesis the folloxxing da^'. Because the stomata are open onl\ at night when it is c()t)l, water loss associ- ated with CAM photosNuthesis is greatlv reduced. This pathwa\' is often found in succu- lents such as cacti and agaxe, and, although C^AM plants are present in the Great Basin, they are a i-elati\eK- minor component of tlie vegetation. Photosxnthetic rates of plants, like most met- abolic processes, sho\\' a strong temperatm-e dependence. UsualK, photosvnthetic rates are reduced at low temperatures because of the temperature dependence of enz^'uie-catah'zed reaction rates, increase with temperature mitil some maximum \alue (which defines the "tem- perature optimum"), and then decrease again at higher temperatures. The temperature optima and niiuimum photosxnthetic rates of plants show considerable variation, and the\' generalK reflect the growing conditions of their natural environments. PHOTOSYNTHETIC adaptation. — In the spring the photosynthetic temperature optima of the dominant shrub species are tvpicalK' as low as 15 C (40 F) (Caldwell 1985), correspcMid- ing to the prevailing en\ironmental tempera- tures (mi(kla\- ma.xima generally less than 20 C). As ambient temperatures rise 10-15 C in the summer, there is an upward shift of only ,5-10 C in the photos\iithetic temperature optima of most shrubs, coupled with a slower decline of photosynthesis at high temperatures. The max- imimi ph()t()s\nithetic rates measunxl in most Great Basin shrubs under either natural or irri- gated conditions range from 14 to 19 jjluioI ClO^ m- s' (DePuit and Caldwell 1975, Caldwell et al. 1977, Evans 1990). These rates are (|uite mode.st compared to t\ie high maxima of 25 to 45 jjLmol CO2 m " s ' ob.sened in man\- warm- dc^sett species adapted to rapid growth at higher temperatures (Ehleringer and Bjorkman 1978, Mooney et al. 1978, Comstock and Ehleringer 1984, 1988, Ehleringer 1985). This presumably reflects the specialization of these Great Basin shiiibs towards utilization of the cool spring growing season. Positive photosynthetic rates are maintained even when leal temperatures are near freezing, which permits photosvnthetic activity to begin in the very early spring (DePuit and Caldwell 1973, Caldwell 1985). Unusuallv high maximmn photosvnthetic rates of 46 ixmol CO2 m ~ s ' have been reported for one irrigated Great Basin shnib, rabbitbrush {Chnjsothamnus nauseosus) (Da\is et al. 1985). This species is also unusual in having a deep tap root that often taps groundwater, unusuallv high levels of summer leaf retention (Branson et al. 1976), and continued photo.sxnthetic activitx* throughout the summer drought ( Donoxan and Ehleringer 1991). All of these characters sug- gest greater photosvnthetic activity during the warm summer months than is found in most Great Basin shrub species. Shoot ACTTIMTY' and phenology. — Gener- ally speaking, there is a distinct drought in early summer (June-|ulv) in the Great Basin Cold Desert, the Mojave Desert, and the Sonoran Desert. All of these deserts ha\e a substantial winter precipitation season, but they differ in the importance of the summer and early fall rainy seas(jn (|ul\-October) in supporting a dis- tinctive period of plant growth and acti\itv (MacMahon 1988). The relationship between climate and plant growing season is complex and includes total rainfall, seasonal distribution of rainfall, and predictabilitv of rainfall in different seasons as important \ariables. Fmthermore, in \en arid areas the seasonalih' of temperatures may be as important as that of rainfall. In the Great Basin, cold winters allow the moisture from low lexels of precipitation to accumulate in the soil for spring use, while hot summer temperatiu'es cause rapid evaporation from plants and soil. High temperatures can prevent wetting of the soil profile bevond a few centime- t(Ms depth in response to sununer rain, even when sununer rain accounts for a large fraction of the animal total (Caldwell etal. 1977). As total annual rainfall decreases, the relative impor- tance of the cool spring growing season i I icreases as the oiiK potential growing period in which available soil moisture approaches the evaporative demand (Thornthwaite 1948, Com- stock and Ehleiintier 1992). Finally, reliabilih 19921 Plant Adaitation 201 of nioisturc is important to [XTcnnials, and as axerage total precipitation decreases, the \ari- ance bet\veen \ears increases (Ehleringer 1985); \ariabilit\' of annuiil precipitation is dis- cussed in more detail later in the section on annuals and life-histor\' dixersitv. Summer rain is more likel\- to be concentrated in a few high- intensit\ storms that max not happen e\eiA' \ear at a gi\en site and ma\' cause more nmoit when the\ do occur. The abilits' of moisture from w inter rain to accumidate o\er several months greatly enhances its reliabilits' as a moisture resource. Thus, most plants in the Great Basin have their priniar\- growing season in the spring and earl\- summer. Some species achie\e an e\ergreen canop\' b\' rooting deepK; but few species occur that specialize on growth in the hot summer season (Branson et al. 1976, Cald- well et al. 1977, Everett et al. 1980). Ehleringer et al. (1991) measured the abilitv of common perennial species in the Colorado Plateau to use moisture from summer convection storms. The\- obserxed that less than half of the water uptake b\- wood\' perennial species was from suriace soil laxers saturated b\' summer rains. Prexalence of summer-active species increases along the border betxveen higher basins and the southeast Mojaxe Desert xvhere summer rain is more extensixe, and especialK' on the Colorado Plateau xx'here summer rain is greatest. Summer temperatures are also lower on the Colorado Plateau than in the eastern Mojaxe (Table 1), alloxxing more effectixe use of the moisture. Most phenolog)- studies, especiallx' from the more northern areas, emphasize the directional, sequential nature of the phenological phases (Branson et al. 1976, Saner and Uresk 1976, Cambell and Harris 1977, West and Gastro 1978, Pitt and W'ikeem 1990). A single period of spring vegetative groxvth is usually folloxved by a single period of floxxering and reproductix'e groxx'th. Manx- species produce a distinct cohort of ephemeral spring leaves and a later cohort of exergreen leaxes (Daubenmire 1975, Miller and Schultz 1987). For most species, multiple groxxth episod(\s associated xxith intermittent spring and summer rainfall exents do not occur. In xears xxith unusually heavy August and Sep- tember rains, a distinct second period of xegeta- tixe growth may occur in some species (West and Gastro 1978). Climatic xariations from xear to xear do not change the primaty importance of spring gro\xi:h or the order of phenological exents. In particular \ears, thex' ma\- cause expansion or contraction of xc^gt^tatixc pluuses and exen the omission of reproductix-e pha.ses. Most species initiate grox\th in earlx' spring (March) xvhen maximum da\time temperatures are 5-15 C and xx'hile nighttime temperatures are still freezing. Delaxed initiation of spring groxxth is generally associated xxith greater summer actixit\- and max- be related to an exer- green habit, a phreatophxtic habit, or occupa- tion of habitats xxith greater sununer moisture axailabilitx from regional rainfall patterns, nmoff, or tirovmdxx'ater. Higher-than-ax-erase xxinter and spring precipitation tends to prolong vegetatixe growth and delax- reproductive groxx'th till later in the sununer ( Saner and U re.sk 1976, Cambell and Harris 1977). Strong xegeta- tive dormancy ma\' be displayed in mid-summer (Everett et al'. 1980, Evans 1990), although root groxx'th (Hodgkinson et al. 1978) and increased reproduction (W'est and Gastro 1978, Exans, Black, and Link 1991) max' still occur in response to rain at that time. In xears with beloxx'-axerage spring and svunmer precipita- tion, leaf senescence is accelerated and floxx'er- ing may not occur in man\- species. The time taken to complete the full annual groxxth cxcle including both xegetatixe and reproductixe stages is stronglx related to rooting depth in most of these conmumities, xxith deep- rooted species prolonging actixit\' further into the summer drought (Pitt and Wikeem 1990). The exact timing of floxx'ering and fniit set shoxvs considerable xariation among different shrub species. Some, especiallx those that are drought-deciduous, lloxxer in late sprin>j; and earlx summer just prior to or concurrent xxith the onset of summer drought. Manx- exergreen shRib species begin floxxering in midsummer (Artonisia) or in the fall {Gutierrczia and Chn/sothainntts). These late-flowering species generallxdo not aj)pear to utilize" stored reserx'es for floxx'ering. but relx on current photo.sxnthe- sis during this least fax-orabk" period. In the case (){ Aticmisia fridoitafa. it has been shoxxn that earlx )lix-drates used to fill fruits arc dcrixcd exclnsixi'lx from the inflorescences theniselxes, xxhile photosxnthate from xegetatixe l)ranches presumablx continues to support root groxx'th. Summer rain during this time period does not promote xegetatixe shoot groxxth but does increase xvater use by and the ultimate size of inflorescences (Exans 1990). Exans, Black, and Link (1991) haxe argued that this pattern of floxx'ering, ba.sed on residual deep soil moisture 202 Great Basin Naturalist [Volume 52 and the unreliable summer rains, ma)' contrib- ute to competitixe dominance within these comnumities. The more favorable and much more reliable spring growing season is used for \egetative growth and coiupetitive exploitation of the soil \olume, while reproductive gro\\i:h is delayed until the less favorable season, and may be successful only in years with adequate su mmer precipitation . Most grasses in the northern part of the Great Basin utilize the G,5 pathway and begin growth very early in the spring. These species complete fruit maturation by early or mid- sunnner, often becoming at least partially dor- mant thereafter. On the Colorado Plateau, with much greater amounts of summer precipitation, there is a large increase in species number and cover by C4 grasses such as bluestem (Andropogon) and grama {Bouteloua), espe- cial K at warmer, lower elevations and on deep sandy soils. Many of these species occur in mixed stands with the C3 species but delay ini- tiation of growth until May or Jime; they can be considered suiumer-active rather than spring- actix'e. In contrast, some C4 grasses such as sand dropseed {Sporoholii.s cri/ptcmdnis), galleta grass (Hilaria jainesiii), and three-awn {Arisfkla purpurea) are widespread in the Great Basin where sunuuer rain is only moderate in long- term averages and veiy inconsistent year to year. Spring growth of these widespread species tends to be slighth' or moderately delayed com- paied to co-occurring C5 grasses, but they are still able to complete all phenological stages based on the spring moisture recliarge. The\' show a greater abilit)' than the G,; species to respond to late spring and simuiier rain witli renewed growth (Everett et al. 1980), however, which compensates in some years for their later developuKMit. Other C4 grasses in the Great Basin may be associated with seeps, streamsides, or salt-marshes, and show a summer activity' pattern. G4 shrubs such as salt- bush (Atriplex) show similar, spring-actixe growth patterns to the (v; shrubs, but may show slightly greater tolerance of sunuuer drouglit (Caldwell et al. 1977). Phenolog)' in the Mojave Desert shows both similarities and strong contrasts to the Great Basin. Although rainfall is largeK biiuodal in the eastern Mojave, absolute amoimts are vvw low. The sunuuer is so hot that little growth normally occurs at that time unless more than 25 nun (1 inch) comes in a single storm (Ackerman et al. 1980). Fall and winter precipitation is the mo.st important in promoting good spring growth of perennials (Beatley 1974). Comstock et al. (1988), looking at one years growth in 19 Mojave species, described an important cohort of twigs initiated during the winter period that accounted for most vegetative growth during the following spring. Although new leaves were produced in response to summer rain, summer growth in many of the species was largeK' a further ramification of spring-initiated floral branches. In most species summer growth made little contribution to perennial stems. Despite the preferred winter-spring orientation of many shmbs, winter recharge is much less effective and reliable in the Mojave Desert than in the Great Basin. Due to warmer temperatures, winter dormancy may be less complete, but vigorous growth rarely occurs until tempera- tures rise further in the early spring. Rapid growth luay be triggered by rising spring tem- peratures or may be delayed until major spring raius provide sufficient moisture (Beatley 1974, Ackenuan et al. 1980). Furthermore, a shal- lower soil moisture recharge often results in fluctuating plant water status and multiple episodes of growth and flowering during the spring and early fall. Some Great Basin species that also occur in the Mojave, such as winterfat and shadscale, commonly show multiple growth and reproductive episodes per year under that climate (Ackennan et al. 1980) but not in the Great Basin (West and Gastro 1978). The degree to which this difference is due entirely to environmental differences as opposed to eco- t\pic differentiation does not appear to have been studied. Water Relations Ai:)APTATION TO LIMITED W.ATER. — Stoma- tal pores provide the pathvx'av by which atmo- spheric COo diffuses into the leaf replacing the CO2 incorporated into sugar molecules during photosynthesis. Because water vapor is present at \eiy high concentrations inside the leaf, opening stomata to capture COo inevitably results in trauspi rational water loss from the plant; thus, leaf water content is decreased, resulting in a decrease in plant water potential (^). Thus, plant water status, transpiration, and ac(juisiti()n of water from the soils have a tre- mendous impact on photosynthetic rates and overall plant grovxth. 1992] Plant AnAPTYnox 203 Main soils in the (Ticat Basin arc liiu^ t(^\- tured, which has botli atKantagcs and disadxan- tages for plant growth. Infiltration of water is slower in fine-textured soils, increasing the like- lihood of runoff and reduced spring recharge, especialK' on steeper slopes. They are also more prone to water-logging and anoxic c-onditions. The deep root systems of Cireat Basin sluMihs are ver\' sensitive to anoxia, and this can be a strong determining factor in species distributions (Limt et al. 1973, CiroeneN'eld and Crowley 1 9S8). Unnsualh' wet \ears ma\' e\en cause root dieback, especially at depth. Once water enters the soil profile, the extremely high surface areas of fine-textured soils with high clav and silt content gi\e them a much higher water-holding capacit\' than that foimd in sandy, coarse-tex- tured soils. Much of this water is tighth' bound to the enormous surface area of the small particles, howe\er, and is released onl\ at \en' negatixe matric potentials. Plants nuist be able to tolerate low tissue water potentials to make use of it. As soil water is depleted during sunuuer, plants reduce water consumption b\ closing sto- mata (DePuit and Caldwell 1975, CambeJl and Harris 1977, Caldwell 1985, Miller 1988) and reducing total canop\' leaf area to a minimum (Bran.son et al. 1976). Evergreen species shed only a portion of the total canop\, however, maintaining the youngest leaf cohorts through- out the drought (Miller and Schulz 1987). Although plnsiological actixit)' is greatK' reduced b\' water stress, exergreens such as sagebnish can still have positive photosviithetic rates at leaf water potentials as low as —50 bars (Exans 1990) and may surxive even greater ](nels of stress. In contrast, crop plants can rareK" sunixe prolonged M^ of less than - 15 bars. Remaining functional at loxx' xx'ater potentials requires the concentration of solutes in the cell sap, and this appears to be accomplished b\ several mechanisms. In manx mesic species, increases in organic solutes may account for most of the change in osmotic potential. In other species, and especialK' tho.se that experience xeiy loxv leaf xvater potentials, a large fraction of the solutes is acquired by the uptake of inor- ganic ions such as K+ (Wvii fones and (^orhani 1986). High concentrations of inorganic ions may l)e toxic to enzx'me metabolism, hoxxexer. and they are xxidely thought to be se(juestered largely in the central vacuole, xvhich accoimts for 90% of the total cell xolume. exen thoush much of the exick^ice for this is (|uite indirect. Nonetheless, the osmotic potential of the cxto- plasm irnist also be balanced or suffer dehxdra- tion. The cytoplasmic .solutes must haxe the special propeitx of lowering the osmotic poten- tial of the cell sap xxathout dismpting enz\nne function or cellular metabolism, and are hence termed "compatible" solutes (W'xii Jones and Gorham 1986). The use of specific molecules shows considerable^ xariation across species apparentlx' due to both species-specific xaria- tions in cell metabolism and taxonomic relation- ships. Some frecjuentlx encountered molecules thought to function in this manner include amino acids such as proline and also special sugar-alcohols. Soiue plants appear to generate low osmotic potentials bx' actixeK" manufactur- ing larger quantities of dissolxed organic mole- cules per cell in response to water st^^ss. a process referred to as "osmotic adjustment."' This process ma\' be costh; hoxx'exer, recjuiring the inxestment of large amovmts of materials (nexv solutes) at a time xx'hen xx'ater stress is largely inhibiting photosvnthetic activitv'. An alternatixe method seems to inxolve dramatic changes in cell xx'ater xolume. Sexeral desert species haxe been obserx'ed to reduce cell xx'ater xolume bx' as much as 80% xx'ithoutxxiltingxx'hen subjected to extremelx' loxx' soil xxater potentials (Moore et al. 1972, Meinzer et al. 1988, Evans et al. 1991). This alloxx'ed the leaf cells to have sufficiently loxv osmotic potentials for xx'ater uptake exen though solute content })er cell xx'as actually reduced. Although total solutes per leaf (and presumablx per cell) decreased, the rela- tix'e concentrations of specific solutes changed (Evans et al. 1991) such that "compatible" solutes made larger contributions to the osmotic potential untk'r stress. Thus, tolerance of loxv leaf xxater potentials was achieved bv a combi- nation of anatonncal and phxsiological special- izations. The anatomical mechanisms inxolxed in this magnitude of xolume reduction and the im]ilied cell elasticitx' haxe not been studied, but tlie process has been shown to be fnllx rexcrsible. Soil texture^ is also an important factor in determining the abilitx' of plant connnunities in a coId-x\int('r climate to respond to summer rain. In areas xxith moderate lexels of precipita- tion, sandx' soils, because of their loxx- xxater- holding capacitx. nsuallx' hold a sparser, more drought-adapted x (^getation than finer-textured ones. In xvarm, arid areas, however, what has been called the "rexerse texture" effect results 204 Great Basin Naturalist [\'oliime 52 ill the more liisli xegetation oceiirrintj; in tlie coarse-textured soils. This occurs because the high water-holding capacit)' of fine-textured soils allows them to hold all the moisture deri\'ed from a single rainfall event in the upper- most layers of the soil profile, where it is liigliK subject to direct e\aporation from the soil. The same amount of rainfall entering a sandv soil, precisely because of its low \\'ater-h()lding capacity', will penetrate to a much greater depth. It is also less likeK' to return to the dning surface b\' capillaiv action. Less of the rain will exapo- rate from the soil surface, and a greater fraction of it will await extraction and use by plants. This inverse-textiu-e effect further restricts the effec- tiveness of summer rains in the fine soils of the Great Basin. The effect is less operative in respect to winter precipitation in the Great Basin, however, because of the gradual recharge of the soil profile to considerable depth under conditions where surface e\aporation is mini- mized by cold temperatures. The combination of much sandier soils and greater amounts of summer rainfall in the region of the Colorado Plateau is largely responsible for the major flo- ristic and ecological differences bet\\'een the two regions. At lower elevations on the south- east edge of the plateau, shiid^-dominated desert scnib mav be replaced by grassland dom- inated by a mix of spring-active C5 and summer- active C4 species. ROOTINC; DEPTH, MORPHOLOGY, AND PHE- NOLOGY.— One of the unique and ecologicallv most important features of the Great Basin shmb communities is not apparent to abo\e- ground obseners. This is the investment of the vast inajorit\- of plant resources in the growth, maintenance, and tunioxer of an enormous root system. The dominant slinibs of the Great Basin usually root to the full depth of the winter-spring soil moisture recharge. Depending on soil tex- ture, slope aspect, and elevation, this is gener- ally between 1.0 and 3.0 m (Dobrowolski et al. 1990). Although this represents a wide range of absolute ck^pths, nianv of the ([ualitatixe pat- terns of rooting behaxior are similar on most of these sites. Ratios of rootishoot standing bio- mass iang(^ from 4 to 7, and estimates of root:shoot annual carbon inxe.stment are as high as 3.5. Most of the shrubs ha\e a flexible, gen- eralized root system with dexelopment of both deep taproots and laterals near the surface. Moreover, it is the categon of fine roots < 3.0 mm in diameter that constitutes 50-95% (Cald- well et al. 1977, Sturges 1977) of the total root biomass. The veiy large annual root inxest- ments, therefore, are not primariK- related to large storage compartments, but to the tunioxer of fine roots and root respiration necessan- for the acquisition of water and mineral nutrients. The fine root network thoroughK' permeates the soil x'olume. Root densities are grenerallv quite high throughout the upper 0.5 meters of the profile, but depth of maximum root devel- opment \aries with depth of spring soil-mois- ture recharge, species, and lateral distance from the trunk or crowai. A particularly high densit)' in the first 0.1 m ma\' often occur, especially immediateh under the shmb canopx (Branson 1976, Caldwell et al. 1977, Dobrowolski et al. 1990). AlternatixeK', maximal densit) mav occur at depths between 0.2 m and 0.5 m (Sturges 1980), and sometimes a second zone of high root densit}' is reported at depths of 0.8 m (Daubenmire 1975) to 1.5 ni (Reynolds and Fralev 1989). Regardless of the precise depth of maximum rooting, sliRib root densit\' is usualK' high throughout the upper 0.5 m and then tapers off, but max continue at reduced densi- ties to much greater depth. The radius of lateral spread is usuallx' much greater for roots ( 1-2 m) than for canopies (0.1-0.5 m). Percent plant coxer abox'eground is often in the neighborhood of 25% xxdth 75% bare ground, but beloxvground the interspaces are filled xvith roots throughout the profile, and root sxstems of adjacent plants xxdll overlap. The perennial grasses that are potentiallv co-dominant xxith shnibs in manx of these communities, such as xxheatgrass {A^ropi/roii sp.), xx'iklne (Eh/nui.s sp.), squirreltail {Sitaiiioii liisti-ix). Indian ricegrass (On/zopsis lu/i)icii()i(h:s). and galleta grass {Hilaiia iainesii), generallx haxe somexxhat shal- loxxer root .sxstems than the shrubs (Branson et al. 1976, Rexiiolds and Fralex- 1989, Dobro- xvolski et al. 1990). Root densities of grasses are often as high as or higher than those of shrubs in the upper 0.5 m but taper off more rapidlx such that shnibs usuallx haxe greater densitx at depth and greater maximum penetratit)n. The moisture resource supporting the great- est amount of plant groxx'th is usuallx- the xx'ater ston^l in the soil profile during the xxinter. This j)r()(ile usuallx has a positixe balance, xxith more XX ater being added bx precipitation than is xxith- draxxn bx' exapotranspiration bet\xeen October and March. As temperatures xx-arm in March, exergreen .species nia\' begin draxxing on this 19921 Plant Ai:)\rT\TK)\ 205 iiioistiiiT resent", ami most species l)eii;iii aetixc growth ill March or ApriL Due to both plant water use and soil-surface exaporation, soil moisture is depleted first in the shallow soil hncM's. As the upper layers dr>', plants withdraw moisture from successively deeper soil hners, a proc(^ss that continues in e\ergreen species throughout the summer until soil moisture is depleted throughout the profile. This progres- sion of seasonal water use beginning in superfi- cial la\'ers and proceeding to deeper soil layers is facilitated In the pattern of fine root growtli, w liicli shows a similar spatial and temporal pat- tern (Fenuindez and (Caldwell 1975, C'aldwell 1976). Root growth generalK precedes shoot growth in the earl\- spring and continues throughout the summer in e\ergreen species, which mav appear quiescent abo\egroiind. In annual budgets of undisturbed communities, .soil moisture withdrawal almost alwaxs approaches measured precipitation o\ er a wide range of annual fluctuations in total precipita- tion, and yew little moisture is lost to runoff or deep drainage beneath the rooting zone (Daubenmire 1975, Caldwell et al. 1977, ('ainbell and Harris 1977, Sturges 1977). Calcu- lati( )ns of the portion of exapotranspiration actu- alK' used b\" plants in transpiration are quite high for a desert enxironment with low percent co\er; they range from 50 to 75% (Caldwell et al. 1977, Cambell and Harris 1977, Sturges 1977). Competition for soil moisture is not neces- saril\- limited to any single season. Plant water stress is highest in late sunuuer, and siir\i\al is most likeK to be influenced at this time, espe- cialK if one plant can deplete residual soil mois- ture below the tolerance range of another. This has been sliown in sexeral cases with regard to seedling establishment (Harris 1977, DeLucia and Schlesinger 1990, Reichenberger and Pvke 1990). Growth and productivits" are more likel\- to be affected in the spring and earl\ summer growing season. This is because most of the years water resource is alread\- stored in the soil in earK spring, and all plants are drawing on a dwindling resene which ultimateK determines growing season length. Competitixe abilits' is often found to be associated with an abilit\ to begin using the limiting water resource earlier in the spring (Eissenstat and Caldwell 19line et al. 1977, Sturges 1980) and are characterized b\ higher water-use efficiencies (DeLucia and Sclilesinger 1990, Smedlev et al. 1991). Shnibs appear to be better than grasses at withdrawing water from deep soil laxers for several reasons. In shallow soils underlain by fractured or porous bedrock, the flexible, mul- tiple taproot structure of a shrub root sxstem ma\" be better suited than the more diffuse, fibrous root system of grasses for following cliinks and clea\age planes to indeterminate depths. This should allow shnibs to better cap- italize on deep, localized pockets of moisture. Unfortunatelv such d\iiamics are rareK studied quantitatixeK because of the difficult\" of mea- suring soil moisture budgets or root distribu- tions under such conditions, but the\' are implicated b\' plant distribution patterns in man\ areas. Indeed, despite the \isiial austeiit\' of such habitats, rooting into major joints and cracks in bedrock outcrops can create sucli a fa\"orable microsite b\' concentration of ninoff in localized areas that ele\ational limits of tree and shrub distributions may be substantiallv lowered as would be expected along riparian corridors or other unusnalK' niesic liabitats (Loope 1977). Even in deep soils, shrubs tend to ha\e deeper root svstems than grasses, but, in addition to this, shiTibs may be more efficient than grasses at extracting deep water. Shiiibs are sometimes able to draw on deep soil moisture to a greater extent than would be predicted from root biomass distribution alone (Sturges 1980), and this is due in part to an intriguing phenom- enon reported b\- Richards and Caldwell ( 1 987), and named b\- them "Indraulic lift." During the Iat(^ spring and earK summer most ol the remaining soil moisture is present in ckn-per soil layers wheic rooting (lensit\ ma\ be relati\eK' low. l^ue to low (k'usities, deep roots alone ma\' be unable to absorb water as (juickl\- as it is lost l)\ the tiaiisi)i ling shoot. During the night, water is actnalK ic^distributed within the soil, flowing from deep soil lavers through the roots and back out into shallower soil laxcrs. This is the phe- nomenon named ■indraulic lift." and the adxantage to the plant is thought to be a reduc- tion in the rootiii'i densitN necessar\' to fully 206 Great Basin Naturalist [N'olume 52 exploit tlie resources of the deepest soil lavers. During the dav, rates of water uioxeiuent from the soil into the roots can be limiting to shoot activit)'. Moistening the upper soil lavers bv noc- turnal h\draulic lift increases the root surface area for al^soiption during the periods of high transpiration. Davtinie water use can he sup- ported by the entire root system and not just b\' the low-densitv deep roots (Caldwell and Ricli- ards f989). The root s\'stems of Great Basin shrubs and Mojave Desert shrubs differ strongly in several ways. (1) Mojave Desert shiiilis often have max- imal rooting densities at soil depths of 0.1-0.3 m, and maximmn rf)ot penetration of 0.4-0.5 m (Wallace et al. 1980). These shallower roots are due to lower rainfall and warmer winter temper- atures resulting in shallower wetting fronts in the soil, and the de\ elopment of shallow caliche layers. (2) Great Basin species have more roots in the shallowest 0.1 m soil laver (Wallace et al. 1980, Dobrowolski et al. 1990). Differences in soil temperatures ha\"e been used to explain these patterns, but the link betvveen cause and effect is less ob\ious in this case, and conjec- tures should be \iewed cautiouslv. Much hotter soil temperatures in tlie Moja\e may be detri- mental to roots in the uppermost few centime- ters during summer, and the rapidly di"ving soil surface may be too ephemeral a moisture resoiu'ce to favor large investments in roots. In contrast, snowmelt and cooler spring tempera- tures may result in less rapid evaporation from the soil surface in the Great Basin and thus fax or more rooting l^v perennials in that zone. (3) Because of the greater soil volume exploited, as well as the high root densitv of Great Basin species, their ratios of rootishoot biomass are al)Out twice that of Moja\e Desert species ( Bamberg etal. f 980, Dobrowolski et al. 1990). Adaptation to salinity. — When annual precipitation levels are much lower than poten- tial evaporation, salts are not leached to an\ great depth, and they can accumulate within the root zone. This is especialK important in associ- ation with particular bedrock outcnps, such as the Nhuicos and Ghinle shales, which release high concentrations of salts during weathering (Potter et al. 1985). Precipitation increases with elexation, and. lollowing major storms or spring snowmelt, there may be surface runoff and recharge of groundwater sy.stems that trans[)ort water from high elexations into closed basins. Streams in the Great Basin usualK terminate in evaporati\e pans where salinities reach extreme le\els and salts precipitate forming a surface crust. The water table near these evaporative pans is often at or ven near the sin-face through- out the \'ear, l)ut, if there is no groundwater flow out of the basin, it too is often quite saline (Dobrowolski et al. 1990). Salinities are lowest on slopes and at higher elevations where precip- itation exceeds evaporative loss, and they increase on more level terrain and in lower-ele- \ation basins where exaporation exceeds pre- cipitation. Sahnities may also be higher in areas where wind-borne materials are transported from saline playas to surrounding slopes (Young and E\ans f 986). These patterns of soil salinitx' are important in determining plant distribu- tions, with more specialized salt-tolerant spe- cies (halophvtes) replacing less-tolerant species repeatedh along gradients of increasing salinit)'. In general, species diversity is low on saline soils. The vast majorit)' of tolerant shrub species in our deserts, and all the shrubs specifically mentioned in this section, lielong to a single plant family, the Chenopodiaceae (goosefoot famiK). Most other important taxa in the saline connmmities are grasses. In the most extreme case of h\persaline salt flats and pans there may be standing water in the wet season with saturating salt concentra- tions. Under such conditions, only microflora consisting of a few species of photosMithetic flagellates, cyanobacteria, and halobacteria are commonly found. The halobacteria appear to be unique in having adapted in an obligate manner to the high salinities of these environments. Thev not only tolerate, but require, high cvtoplasmic salinities for membrane stability and proper enzymatic function (Brown 1982). In strong contrast to this, algae and all higher plants growing in hvper-saline environments show severe inhibition of enzvnne fvmction at high salinity, and thev must compartmentalize salt-sensitive metabolic processes in celhdar regions of low ionic strength ( Muuus et al. 1982). The best definition of a liahphvte is simply a [)lant tolerant of soil salinities that would reduce the gi'owth of unspecialized species. This is .somewhat circular, and that reflects our lim- ited understanding of how halophv tes do what thev do. Halophv tes are more likely to use Na+ in their tissues for osmotic adjustment, while glvcophvtes are more likely to have high K+ ( Ilellebust 1976, Flowers et al. 1977), but there are munerous exceptions. Other differences 1992] Plant Ai:)aptatk)n 207 max he nunc (juaiititatixc than (|iialitati\ c \ ar- ious aspects of mineral nutrition in halophx tes are less sensitixe to high soil salinities, hut unique mechanisms to achiexe this tolerance ha\e rareK' heen identified. It is wideK held that the ahilitv to compartmentalize salts and restrict high Na+ concentrations to the \acuole is of crucial importance (Cakh\'ell 1974, Flowers et al. 1977, linens and I.arhtM" 1982). This conclu- sion is hased primariK- on indirect e\idence of low enz\nne tolerance of salinitv; howexer, rather than direct measurements of actual salt compartmentalization (Munns et al. 19S2, Jefferies and Rudmik I9S4). Haloplntes differ in which ions reach high tissue concentrations when all plants are grown on the same medium (Caldw^ell 1974). Some will concentrate C1-, for instance, while others concentrate S04~'. These differences do not necessarih' determine plant distrilnitions, such as occurrence in soils dominated h)' NaCl \'ersus NaSOa, but rather seem to reflect different reg- ulatoiA' specializations in plant metabolism (Moore et al. 1972). A strong requirement for a uni([ue composition of soil salts is the exception rather than the mle, and the most important effect of soil salinitv' seems to be a disniption of plant water relations from low soil osmotic potentials rather than toxic effects of specific ions. Halophvtes tolerate these conditions bx' ha\ing better regulatoiA' control o\er ion mo\e- ment within the plant, ion compartmentaliza- tion at both tissue and subcellular lexels, and better homeostasis of other a.spects of mineral nutrition in the presence of ver\' high Na-K. Salinit\ poses three major problems for higher plants. First, salts in the .soil solution contribute an osmotic potential depressing the soil water potential, and this ma\' be aggra\"ated as salts become concentrated with soil drving. E\en when sul)stantial moisture is present, [)lant tissues must endure \ t-n low water poten- tials to take it up, and this recjuires a specialized metabolism. Second, an\' salts entering the plant with the transpiration stream will be left behind in the leaf intercellular fluids as water ('\a])()- rates from the leaf. This can result in salt buildup in the intercellular solution causing water moxement out of the cells and leading to cellular dehxdration. Third, salts entering the cxtoplasm in high concentration will disrupt enz)ine function. Haloph\1:es are able to deal with all of these factors over a wide range of soil 1. . . salinities. Haloph\tes show a greater capacit\' for osmotic adjustment, and positixe phot()s\n- thetic rates can be measured in the leaxes of man\ haloplntes at leaf water potentials as low as -90 to - 120 bars (Caldwell 1974), well below the range that would result in death of e\en desert-adaj)ted gl\coph\tes. Tliis is accom- plisluHl in part 1)\' transforming the available salts in the enxironment into a resource and using them for osmotica in j)lant ti.ssues (Moore et ak 1972, Bemiert and Schmidt 1984). Many haloplntes actualK show stimulation of growth rates at moderate^ en\ ironmental salt levels. Halophvtes too must deal with the problem of salt buildup in the leaves, and the\' do so by a wide \ariet\' of processes. There is a great deal of interspecific \ ariation in which method! s ) are used. All the methods appear to incur substan- tial energetic costs associated with maintaining high ion concentration gradients across key membranes (Kramer 1983). Exclusion of salts at the root is possible; this is the method most employed by winterfat (Ceratoides Janata). Salt- bush (Atriplex spp.) has specialized hair-blad- ders on the leaf surface into which e.xcess salts are actively pumped. The hairs e\'entualK' nip- ture, excreting the salts to the outside. Other plants may transport salts back to the root \ia the phloem. Man\- plants exhil)it increased leaf succulence when growii under high salinit\; and this increase in cell xolume can create a sink for salts within the leaf without raising salt concen- trations or furtlier lowering leaf osmotic potential. hi strong contrast to the exident importance of temperature and rainfall pattern in favoring C:5 versus C4 grasses, Ci shnibs tend to belong to edaphic comnumities as.sociated with saline soils. The same species ma\' occur in both warm and cold deserts, and in areas with both winter and summer rainfall patterns. This is an intri- guing difference, but the phwsiological basis linking C, shrubs with high salinitv' is less well understood than the tradeoffs associated with temperature and controlling C5 and C^ grass distributions. Sjx'cies number and percent cover b\ shrubs sucli as saltbush {Ahiplcx spp.) and inkA\'eed (Siicda spp. ), wliich possess the C4 pathwav, usualK inc-rc^ise drainaticallv with increasing salinitv on w(41-drained soils. In marshx' habitats or soils with a shallow, saline water table, howex er. haloplntic (>-, species such as pickleweeds {Allen rolfia spp. and Saliconiia spp.) and greasewood [Sarcohatus ver- micnloicles) regain dominance. It has been sug- gested that hitrher water-use efficiencv bv C4 208 Great Basin Naturalist [\ nluiiie 52 species niav be acKantageous on saline soils to help avoid salt bnildnp in the leaf tissues. How- ever, it has not been showii that transpiration rate is an important factor controlling salt buildup in the leaves of halopln tes when com- pared wath other regulaton' mechanisms (Osmond et al. 1982), nor does this Inpothesis explain the dominance of C3 species in wet saline soils. In the greasewood and pickleweed commimities, soil salinities are extreme, but soils remain wet throughout the growing season, or else groundwater is available within the root- ing zone (Detling 1969, Hesla 1984). As a con- sequence, plant water potentials do not reach the extreme low values of the saltbush commu- nities. Over a wide range of soil salinities, plants such as greasewood appear to draw on readily available deep soil moisture, and high leaf con- ductances are maintained throughout the summer (Hesla 1984, Romo and Hafercamp 1989). The highest whole-plant water-use rates may occur in the presence of high soil salinitv" in mid-summer (Hesla 1984). The communities in which C4 shRil:)s are most prevalent have summer stress from both high soil salinitv and mid-sunnner soil water depletion combined. These species reach much lower plant water potentials during summer than either nonsaline communities or wet-saline ccnnmunities. The role of C4 pliotosviithesis in tolerating these conditions remains to be determined, but it could he related to avoiding excessively low leaf water potentials either liy (1) retarding soil moisture depletion, which both lowers the soil matrix potential and concentrates soil salts, or (2) avoiding exacerbation of low soil water potentials due to high flux rates and large water potential gradients between the leaf and root. Water mo\ement in the x-xlem occurs under tension, and anatomical features that avoid cav- itation in the xylem at extreme]\ low water potentials usually reduce the hydraulic conduc- tivity of the x"\'lem per unit cross-sectional area (Davis et al. 1990, Speny and Tyree 1990). Low specific c()nducti\it\' of the xTlem will, in turn, predispose the plant system to large water potential gradients between roots and shoots, causing an even greater depression of leaf water potential. This problem could be ameliorated either by increased cross-sectional area of the xylem by increased allocation to wood growth, or by features such as C.| photos\Tithesis that reduce the flux rate of water associated with photosN nthetic acti\it> under warm conditions. Nutrient Relations Acquisition of mineral nutrients. — Apart from the veiy high elevation montane zones, water appears to be the most limiting resource in the Great Basin and Colorado Pla- teau communities. Productixit) is usualK well correlated with yearlv fluctuations in precipita- tion and spring moisture recharge over a wide range of \alues (Daubenmire 1975, Kindschy 1982), and competitive success has more often been associated with soil water use patterns than nutrient budgets. Nonetheless, addition of mineral fertilizer sometimes does result in modest increases in producti\it\', and studies ha\e shown strong effects of neighboring plants on nutrient uptake rates (Caldwell et al. 1987). These dynamics have been less studied than have plant water budgets, and broad ecological relationships are just now being worked out in detail. Nutrient acquisition has been showni to be a major factor determining communits' com- position only in veiy special habitats such as large sand dunes (Bowers 1982) or unusual bed- rock (DeLucia and Schlesinger 1990). MiCROPHYTIC CRUSTS. — Throughout the Great Basin and Colorado Plateau, it is common for the exposed soil surface to l)e covered by a complex connniuiit\' of nonvascular plants including dozens of species of algae, lichens, and mosses (West 199()). These organisms often form a biotic ciTist in the upper few centimeters of the soil and, when undisturbed, may result in a vei"y conx'oluted microtopograplu' of the sur- face. While a detailed discussion of the microplutic crusts is bcNond the scope of this review, it is important to realize that percent cover by such crusts often exceeds that of the vascular plants, and their contribution to total ecosvstem prochicti\itA' is consitlerable. Perhaps most important to co-occurring \ascular plants are the nutrient inputs to the soil b\' nitrogen- fixing cnist organisms (c\anobacteria and lichens). These inputs will be particularlv important in the cold deseit where fewxascular plants form sMiibiotic relationships with nitro- gen-fixing bacteria. Nurse plants and fertile islands. — In man\ des(Mt areas, including both the Mojave and the Great Basin, establishment of newindi- \iduals may occur preferentialK' under the exist- ing canopies of alreadv established indi\iduals. Tliese pre\iousl\' established indixidnals mav tlieu be referred to as nurse plants. Preferential 1992] Pl.WT Ai:)MT\TION 209 estahlisliiiK'nt inulcr iiiirsc plants nia\ ocfiir in spite of the fact that 759ic or more of tiie gromid area nia\' he liare interspaces b(^t\\'een plant canopies. The phenomenon can he important in both steadx-state commnnitA cl\ namics and also snccessional patterns following distnrbance (Wallace and Ronme\- 1980, Exerett and Ward 1984). Two .somewhat distinct factors contiibntc^ to the nnrse-plant phenomenon. The first has to do the with beneficial effects of partial shading and rednced wind nnder existing canopies resulting in cooler temperatnres and possibK' moister soil conditions in the snrface huers. These interactions depend directk- on the pres- ence of the nnrse plant in creating a fa\orable microsite, and ha\e been studied with particular reference to pin\on and juniper establishment in the Great Ba.sin. A second factor inxoKes the creation of fertile islands bv the prolonged occu- pation of the same microsite b\' man\' genera- tions of plants; this can make the fertile island a preferred site even if the previous occupant is alreacK deceased. This microsite impro\'ement occurs due to preferential litter accumulation and more e.xtensixe root growth directK under a plant canopw and deposition of aeolian mate- rials under reduced wind speeds in plant cano- pies. In time, soils nnder existing plants mav come to be slightK' raised above the interspace level, have a lighter, loaniier texture, higher organic matter content and better soil structure, less surface compaction, better aeration and more rapid water infiltration, and/or higher l('\els of available mineral nutrients than immediatelv adjacent interspace soil (A'est 1962, Wood et ai 1978, Homnev et al. 1980, Hesla 1984, West 1989, Dobrowolski et al. 1990). Direct effects of nurse plants and indirect effects of fertile islands should complement and reinforce each other in maintaining selective spacial patterns of seedling establishment. Sur- face soil nnder haloplntes mav also show- increased salinitv (Richard and (]line 1965) due to excretion ol excess salts bv the canopv or translocation and re-excretion Ironi the roots. DiXER.SITY OP^ Ghowtii Foinis One of the striking features of the cold desert vegetation is the uniformlv low stature of the vegetation. This is undoubtedlv due to several factors, and few studies have specificallv addressed the role of plant stature in these com- munities. Since low temperatures mav limit photosx nllicsis in tlic cool spiiirj;. and earlier growth on limited soil moisture resen(\s mav be c-()mp(titi\c'l\ advantageous, occupving warm microsites mav be favored. Substantial increases in air temperature and reductions in wind speed will exist in the lowest meter next to the ground, and especiallv in the lowest decimeter. Low cushion plants oi- low. dense shrub canopies should have vvarmei" spring leaf temperatures by virtue of being short and bv virtue of leafing out first in a dense clump of old dead leaves and twigs ( Smith et al. 1983, Wilson et al. 1987). This advantage mav be partiallv offset by overlv high temperatures in summer for species remaining active all sununer. Stature is also likelv to affect aeolian deposit of materials under the shrub canopies (W^ood et al. 1978, Young and Evans 1986), snow accumulation (Branson et al. 1981, West and Caldwell 1983), and the likelihood of winter desiccation under cold, windv conditions (Nelson and Tienian 1983). All of these could be important factors, but few detailed studies have been done. Having considered tlie relationships of the dominant plant habits and phenologies to cli- mate, it is perhaps instructive to consider whv .some of the other famous desert life forms are so poorlv represented in this region. Three life forms vvliich are prominent features of the warm desert but inconspicuous elements of the cold desert are (1 ) large CAM succulents (e.g., cacti and agave), (2) opportunistic drought-decidu- ous shnibs specialized for rapid knif-flnshing, and (3) animals. Definitive work explaining the structural nnilormitv of the vegetation is not available, but the environment is well enough understood to identifv at least some of tlu^ likelv causes. CAMSrcci'I.KXTS — Most of the large C.\.\I succulents are not tolciant ol freezing temper- atures, and most extant species would be excluded from the (jrcat Basin bv this factor alone. Thei'e ai"e, however, a sulfitienl mimbcr of species which have adapted to tolerate cold temperatures that we are justified in asking whv thev have not undergone more adaptive radia- tion, or claimed a more prominent role in these communities. The most important factor limit- ing this life form is probably the importance of the cool spring growing season. CAM succu- lents generallv ( 1 ) allocate ven little biomass to root (root/shoot ca. 0.1), (2) are shallow rooted, (3) store moderate-sized (compared to soil v\ater-liolding capacitv ) water resenes inside 210 Great Basin Naturalist [Volume 52 their tissues wheu water is available in the sur- face soil layers, and (4) use their stored water in photosynthesis with unparalleled water-use effi- ciency by opening their stomata only at night when temperatures are cool (Nobel 1988). They are fa\ored bv (1) very warm days (30-40 C), which allow them to have higher photosyiithetic rates and cause competing species to ha\-e very low water-use efficiencies; (2) large diunial tem- perature fluctuations allowing for cool nights (10-20 C) which allow them to have high rates of CO2 uptake with high water-use efficiency; and (3) intermittent rainfall \\'hich onl\' wets the upper soil layers so that the limitations of their shallow roots and water-hoarding strategy are compensated foib\ the ephemeral natiu-e of the soil water resoiu'ce. These conditions are some- what poorK" met in the cold desert. The impor- tant water resource is one of deep soil recharge that favors deep-rooted species and confers much less advantage on internal water hoarding. Freezing tolerance in CAM succulents appears to be associated with low tissue water contents, and this mav inhibit uptake of water when it is plentiful in the siu-face layers in the thermalK' x'acillating eark' spring (Littlejohn and Williams 1983). Furthermore, water-use efficiencies of C3 and C4 species are quite high in the cool spring. Nonetheless, even moderate amounts of summer rain in the southern and eastern por- tions of the Great Basin result in numerous species of cacti. Due to the open nature of the understoiy, many of these species ha\e a large elevational range, and they are often more common in the pinvon-juniper or even the mon- tane zone than on the desert piedmont slopes. Almost all of these cacti are small, usually 5-20 cm liidi, with a small, globose (e.g., Pediocactiis siinpsonU), prostrate (e.g., Opiintia pohj- cantha), or low, caespitose habit (e.g., Echinoccreus tn<4ochidi(itus). This allows them to take acKantage of the warmer da\time tem- peratures near the ground in the sj^ring and facilitates an insulating snowcover during the coldest winter periods. The number of and total cover by cacti increase considerabK with increased summer rainfall on the Colorack) Pla- teau, but oulv in the eastern Mojave with both summer rain and warm spring tempcratun^s do we find the larger barrel-cactus (e.g., Fcrocddiis acanfhoidcs) and tall, shnibb)^ chollas (e.g., Opinilid (ic(i)ithiH'arpa). Opportunistic drought-deciduous / MULTIPLE LEAF-FLUSHING SPECIES. — This habit, like that of the succulents, is favored by ( 1 ) intermittent rainfall wetting only shallower soil layers, and (2) warm temperatures allowing for rapid leaf expansion in response to renew/ed soil moisture. Again, these requirements are not well met in the Great Basin. The priman' mois- ture resource is a single, deep recharge in the winter. Most shiaib species are deep rooted, and rather than experiencing \acillating water avail- abiHtv', they have actixe root grow1:h shifting to deeper and deeper soil kners during the season, thus producing a gradual and continuous change in plant water status. This allows manv spring-active shrubs to remain partially ever- green throughout the summer, and, in regions where it occurs, the\' are able to make rapid use of anv moisture availalole from simimer precip- itation without the need for renewed leaf pro- duction. The only shrub reported to ha\'e )iiultiple leaf flushes in response to late spring or summer rain in the Great Basin is the dimin- utive and shallow^- rooted Artemisia spinescens (Everett et ak, 1980). Some species found in the Great Basin are reported to have multiple growth c\'cles/year where they occur in the Mojave (Ackerman et ak 1980). ANNUALS AND LIFE-HISTORY DIVERSITY. — The spectacular wildflower show^s displayed in favorable years in the Mojave Desert do not occm- in the cold desert of the Great Basin (Ludwig et ak 1988). Annu;il species are few in nimiber, and, except in earK" succession after fire in woodlands or on \en disturbed sites, the)' rarely constitute a major fraction of total com- munit>' biomass. This is undoubtedly related to sexeral complex factors, but various aspects of precipitation patterns are likeK' to be among the most important. To begin with, the paucits' of summer rain in some parts of the Great Basin ma\ largeh' eliminate an entire class of C4 siuumer annuals important in the floras of other regions including the Cok)rado Plateau. Other aspects than seasonalih' are also cnicial, how- e\er. Ver\ low means oi annual precipitation are conunonh' associated with large annual floras, but correlated with low mean precipitation is high \ear-to-\ ear \ariation in precipitation which some authors have argued is equally important. The coefficient of xariation (CV) in precij)itation shows a r(4ationship to mean pre- cipitation in the (wvat Basin and Colorado Pla- teau (Fig. 2) veiv similar to that found in warm 19921 Plant Ad AinviioN 211 0.7 o 0.6 t ■ m ';z O.S ro > B 0.4 , ■ r CD 0.3 o ■ , CI) 0.2 o O 0.1 , 1 - T 1 3 r2 = .57 - O - \oO cj^ s ° o ^ o o°o ^ — ~-- o o - " 0.0 100 200 300 400 500 Mean annual precipitation, mm Fig. 2. The relatioii.ship hctween mean precipitation and the \ariabilit\' of rainfall between years as nie;isured h\- the coefficient oi \ariation in annual precipitation. The data inchide points scattered throughout the Great Basin in Utali and Xe\ada and the Colorado Plateau in Utah and Arizona. The line shown is the least squares best fit for the data: C\' = 1.27 - 0.403 ° log(niean annual precipitation, mm) {ii = 69 sites./) < .001). deserts (Ehleringer 1985). Although mean pre- cipitation has tlie greatest single effect, there are. aclclitionalK; important geographic influ- ences on the CV of precipitation which are independent of mean precipitation. A multiple regression of the CV of precipitation on logdnean annual precipitation), latitude, and elexation in the Great Basin has an r of .81 and indicates that each \arial)le in tlie model is highl\- significant (j) < .001 or better). For a given mean precipitation, the C\^ increases with decreasing altitude in the Great Basin, but an ind(^p(Mident effect of elevation was not signifi- cant in the Colorado Plateau. The CV also increases from north to south in the Great Basin and increases from south to north in the CJolo- rado Plateau, which results in a latitudinal band of greatest annual \arial)ility nuniing through southern Nevada and Utah. This l)and is related to two major as]:)ects of regional climate. Mo\ing southward in the Great Basin, temperatures gradually increase, favoring moister air masses and more intense storms, but sites are morc^ remoxed from the most common winter storm tracks, and the number of rainv daws per Near decreases (Houghton 1969). Moving northward from Arizona and New Mexico, the southern Nevada and Utah band of highest precipitation variabilit\- also corresponds to the northenunost extent of summer storms associated with tlie 0 2 0 3 0 4 CV for mean annual precipitation F"ig. 3. The relationship between relial)ilit\- of annual precipitation and life-histon' strategy of herbaceous plants. The site with greatest representation of annuals is Deadi \'allev in the Moja\e De.sert, the second highest is C^auNon- lands in the Colorado Plateau of southeastern Utah, and the other three sites aie Great Basin Cold Desert or shrub- steppe (data were collected b\' Kim Haiper and pnniously published in Schaffer and Gadgil 197.5). Arizona monsoon, and the region where the fraction of summer rain increases substantially moving southward. This zone also has some of the most arid sites of the entire region located along the transition to the Mojave Desert in southern Nevada and the canyon countiy of southeastern Utah, and these sites can be expected to have the highest variabilit\ due to both low mean rainfall and geographic position correlated with rc^gional weather patterns. Becau.se the (ireat Basin and Colorado Plateau are only .semiarid, the CV ol annual precipita- tion is not usually as high as in manv of the more arid warm deserts (Beatley 1975, Ehleringer 1985), but particular sites may be both arid and highlv unpn^dictable. Ilaiper (cited in Schaffer and Ciadgil 1975) found that the prevalence of annuals was posi- ti\eK associated with the C\' in annual precipi- tation for five sites located in the Great Basin, Colorado Plateau, and Moja\e Desert (Fig. 3). The largest annual populations occurred in Death Valley (Mojave), followed by Canyon- lands (Colorado Plateau in southeastern Utah). One inteipretation of this relationship is that high \ariabilit\- in total precipitation between vears mav be associated v\ ith high rates of mor- tality and therefore favor earlv reproduction and an annual habit (Schaffer and Gadgil 1975). Manv desert annuals are facultativ elv perennial in better-than-averaee vears, and some have 212 Great Basin Naturalist [Volume 52 perennial races or sister species (Ehleringer 1985). The dynamics and distributions of these closely related annual and perennial taxa should receive further study in regard to their expected life span, reproductive output, and relationships to climatic predictability'. Another perspecti\'e is to ask how competition between very distinct shnib and annual species is affected by precip- itation variability. While in many respects com- plementaiy with the optimal life histoiy arguments, this approach emphasizes how large differences in habit affect resource capture and competition rather than focusing on subtler dif- ferences in mortalit)' and reproductive sched- ules. The lower variability of precipitation in much of the Great Basin compared to the Mojave and Sonoran deserts, as well as the more reliable accumulation of moisture during the winter-recharge season, may favor both stable demographic patterns and growth of perennials. Annuals tend to be shallow rooted (most roots in upper 0.1 m depth), and they are poorly equipped to compete with shrubs for deep soil moisture. If shrub density is high, and years of unusually high mortality' are rare, then shiaibs may largely preempt the critical water and min- eral resources and suppress growth of annuals. The dominant shrubs of the warm deserts do not have high root densities in the upper 10 cm of the soil profile (Wallace et al. 1980), have lower total root densities, and have lower total cover when compared with Great Basin perennials. Annuals are therefore likely to experience more intense competition from shnibs in the Great Basin. This conjecture is finther supported by considering that perennials in the Great Basin generally transpire 50% or more of the ammal moisture input over a wide range of yearly vari- ations. In the Mojave this fraction may average only 27% and vary between years from 15 to 50% at the same site (Lane et al. 1984), or even be as low as 7% (Sanimis and Gay 1979). The reduced overlap in rooting profiles and the greater availability of unused moisture resources may have favored the development of annual floras in the Mojave Desert more than in the Great Basin. With severe distin-bance from grazing and other anthropogenic activities, exotic annual species have invaded many Great Basin communities. Once established following distiubance, these annuals are not always easily displaced by short-tenu shrub succession. While this discussion has been presented in the con- text of annuals versus perennials, tradeoffs lietween short- and long-lived perennials may be influenced by very similar climatic parameters, sometimes operating over different time scales. Other factors that may be important in the ecolog)' of Great Basin annuals include the effects of the very well developed ciyptogam soil cRists or vesicular horizons on seed preda- tion (abilit)' of seeds to find safe sites), seed germination, and seedling establishment. The restriction of winter growth by cold tempera- tures could also be of crucial importance, inhib- iting the prolonged establishment period enjoyed by winter annuals in warm deserts. Fall germination followed by low levels of photos)ii- thesis throughout the mild winter is essential for \igorous spring growth of winter annuals in the Mojave, and, while heavy spring rains may cause germination, such late cohorts rarely reach maturity (Beatley 1974). Annuals are common in transition zone sites of the ecotone between Mojave Desert and Great Basin plant commu- nities in southern Nevada, but associated with changes in perennial species composition along decreasing mean temperatiu'e gradients in that region are decreases in annual abundance (Beatley 1975). Literature Cited Ackerman. T L., E. M. Romney. A. Wallace, and J. E. KiNNEAR. 19S0. Plieiiolog}- of desert shnihs in south- em Nye County, Nevada. Great Basin Naturalist Mem- oirs 4: 4-2.3. Bamberg. S. A.. A. Wallace. E. M. Romney. and R. E. Hunter. 1980. Further attributes of the perennial vegetation in the Rock \'alle>' area of the northern Mojave Desert. Great Basin Naturalist Memoirs 4: 37-^39. Be.atley, J. C. 1974. Phenological events and their emiron- mental triggers in Mojave Desert ecosystems. Ecologv' 55:856-S6.3. . 197.5. Chmates and vegetation patterns across die Mojave/Great Basin Desert transition of southern Nevada. American Midland Naturalist 93: 53-70. Bennert. H., and B. Schmidt. 1984. On the osmoregula- tion in Atiiph'x hi/mcnehjtra (Torr.) Wats. (Chenopodiaceae). Oecologia62: 80-84. BiLLiNCS, W. D. 1949. The shadsctJe vegetation zone of Nevada and eastern California in relation to climate and soils. American Midland Naturtrlist 72: 87-109. Bowers, J. E. 1982. The pkuit ecology- of inland dunes in western North .America. Journal of Arid Environments 5: 199-220. Branson. F. A., G. F. Gieeord. K. G. Renard. and R. F. Hadley. 1981. Rangeland hydrology-. Kendail/Himt Publishing, Dubuque, loyva. Branson, F. A^ R. F, Miller, mid I. S. McQueen. 1976. Moisture relationships in twelve northern desert shrub connnunities near Cirand (unction, ("olorado. Ecology 57: 1104-1124. 19921 Plant Adaptation 213 Bhikns M.. and F. L\i;iii:h 19S2. Osnunt'i^ulation in lialo- plntic liigher plants: a t<)nipiu"ati\'e shiclN' of solnblc caiholndrates, polvols, hetaines and free proline. Plant Cell and Environment 5; 2S7-292. Bkown, a. D. 19S2. Halophvtic prokar\otes. Passes 137- 162 in O. L. Lange. P. S. Nobel. C. B. Osmond, H. Ziegler, eds., Encvclopedia of plant ph\siolog\-. New- series. \'ol. 12C. Springer-V'erlag, New York. Caldwell, M. M. 1974. Phvsiologv- of desert halophvtes. Pages 35.5-377 /;i R. f. ReimoldandW. H. Queen, eds.. Ecolog\ of lialoplutes. Academic Press, New York. . 1976. Root extension luid water absorption. Pages 63— S5//i O. L. Lange, L. Happen. E. D. Schulze. Water and plant life. Ecological Studies. Analyses and SMithe- sis. \'ol. 19. Springer-V'erlag, New York. . 1985. Cold desert. Pages 19.V212 in B. F. Cliabot and H. A. Moonev, eds.. Physiological ecologN'of North .American plant communities. Chapman and Hall Ltd.. London. C.\LD\VELL. M. M., and J. H. I^ICH.xkds 19S9. Ihdraulic lift: water efflux from upper roots improves effective- ness of water uptake by deep roots. Oecologia 79: 1-5. Caldwell, M. M., J. H. Rk:il\rds. J. H. M,\nw.\ring. and D. M. Elsenst.at 1987. 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Received 17 August 1992 Accepted 25 October 1992 Creat Basin Naturdist 52(3), pp. 216-225 LIFE HISTORY, ABUNDANCE, AND DISTRIBUTION OF MOAPA DACE (MOAPA CORIACEA) G. Gaiv Scoppettone , Howard L. Biirt^e ", and Peter L. Tuttle ' ' Abstract — Moapa dace {Moapa roriaccii) is a teder;iliv listed endangered fish endeniie to the spring-fed iieadwaters of die Muddv River, Clark Connty, Nevada. Speeies life history; abundance, and distribution were studied from March 1984 to JanuiUT 1989. Reproduction, which was obsei"ved yetu-round, peaked in spring and was lowest in fall. It occurred in headwater tributaries of the Muddy Ri\er, within 150 ni of warm water spring discharge in water temperatures ranging from 30 to 32 C. Feni;iles matured between 41 and 45 mm in fork length (FL). Egg abundance increased with female size (r" = .93); counts ranged from 60 for a 45-mm-FL female to 772 for one 90-mm FL. The oldest of eight fish, aged by the opercle method, was a 90-mm-FL, 4+-year-old female. Adults are omnivorous but tended toward caniivory'; 75% of matter by N'olume consumed was invertebrates and 25% pkints and detritus. Fish size was generally commensurate with flow, the largest fish occurring in the greatest flow. Adults were near bottom, in focal velocities ranging from 0 to 55 cm/s. Jn\'eniles occupied a narrower range of depths and velocities thim adults, and lai^vae occupied slack water. From December 1984 to September 1987, the total adult population ranged from 2600 to 2800. Although these numbers are higher than prexiouslv believed for Moapa dace, they are still sufficiently low to warrant its end;uigered status. The dependency of Moapa dace s different life histoiy stages to \arious areas and habitat t\pes of the Warm Springs area suggests that all remaining habitat is necessary for their sumval. Ki'i/ icord.s: Moapa coriacea, Moapa dace, life liislonj. rcpnulniiioti l)iolo^y.jccmi(littj. agc-i^n>ictli,Jo(Hl habits, habitat use, bodij size, Mitdch/ Riiei; Nevada. Tlie Moapa dace [Moapa coriacea) i.s a tlier- mophilic niiniiow endeniie to the Mndd\' Ri\ er system, Clark Counts, Nexada. First collected in 1938, it has lustorically been relegated to the headwater area where the Miiddv River origi- nates from a series of warm springs (Hubbs and Miller 1948). La Rivers (1962) cafled the Moapa dace and its coinhabitant, Moapa White Ri\er springfish [Crenichthijs baileiji nioapac), ther- mal endemics becanse of their apparent affinit\ for warm water. Rarely exceeding 12 cm in iork length (FL), Moapa dace ha\e moiphological similarities to ronndtail chnb (Gila roJ)iista) and speckled dace (Rliinichtlujs osctiln.s), wliich also inhabit the Muddy River (Hubbs and Miller 1948). They are more similar, however, to the genus Agasir/, which occurs in other lower Col- orado River drainages; the two genera are spec- ulated to have a conunon ancestor (Hubbs and Miller 1948). Moapa dace are distinguished In small embedded scales and a bright black spot at the base of the caudal fin. Little was known of Moapa dace life histor\ prior to this studv La Rixers (1962) identified them as methodical schoolers; a curson' gut examination bv him indicated that they foraged primariK' on arthropods and some vegetative matter. In a systematic sampling effort, Deacon and Bradlev (1972) collected Moapa dace in 28-30 C water; one specimen was collected in 19.5 C water. Within the confines of its limited distribution, Moapa dace ha\e been captured in a variety of habitats, including spring pools and slow- to fast-mo\ing water, and in association with \arious substrates and submergent \egeta- tion (Hubbs and Miller 1948). l^ast ichtlnofaimal siuvevs suggested a declining Moapa dace population (Deacon and Bradle\' 1972, Cross 1976). These suivevs were ([ualitatixe and produced neither an estimate of the number of dace remaining nor the relati\e population decrease between suneNS. Ono et al. (1984) tliought that ouK sexeral lumdred M()a[)a dact^ persist(xl and that their distribution had been hirtlier restricted within the alread\ liiiiited historic habitat, conlininsj; them to the nj.S. Fish and Wildlife Senitc, Nation.i ^Present address: U.S. Tisli and W iMIil,- ■^Present addirss; U.S. Kisli and W ildlil, (<-s.'aivhC:rii .(.rsli.ik FisKr ■ at H.isin ( ni . Siilistatliai, H.-iio. Nrvada. L'S.X Sm02. .tancvOrinr. Misalika. Idalui. L'S,\ S:«2(). •nn, NiA.id.i, i:s\ S9.5()2, 216 19921 MOAPA Dace 217 main stem of the upper Muddy River and a semi-isolated headwater spring system about 130 m long. The puq)ose of this study is to expand information on Moapa dace life histon\ abundance, and distribution. Life histoiy infor- mation includes reproductiye biologv', habitat use, food habits, and age and growth. Study Area The Mudd\' River is at the northern edge of the Mohave Desert, where average annual pre- cipitation is 15 cm usualK^ in the form of rain. Caipenter (1915) described historic terrestrial vegetation which included greasewood {Sarcohatus vennicidatiis), shadscale (Atriplex confei'fifolia), creosote bush {Larrea triclen- tata), and mescjuite (Prosopis .sp.). Stream banks were lined with willows {Salix sp.), screw-bean (Prosopispubescens), cottonwood (Populus sp.), and mesquite (Carpenter 1915, Harrington 1930). Prior to the completion of Hoover Dam (aka Boulder Dam) in 1935, the Muddy (aka Moapa) River was about 48 km long and dis- charged into the Virgin River, which joined the Colorado Rixer (Hubbs and Miller 1948). Today, it is about 40 km long and discharges into the Overton arm of Lake Mead (Fig. 1). Source springs of the Mudd\ River probably originate from Paleozoic carbonate rocks (Garside and Schilling 1979) and occur within a 2-km radius. As is t}pical of warm springs, the water is rela- ti\ely rich in minerals. Garside and Schilling (1979) list sodium and calcium as predominant cations, and carbonate and sulfate as predomi- nant anions; total dissolved solids were 854 ppni and pH was 7.7. Water emerges at 32 C and cools and increases in turbidit)' downstream (Cross 1976). Although spring discharge is rela- tively constant at about 1.1 mVs, the Mudd\ Rixer flow fluctuates because of rain, agricul- tural diversions, e\aporation, and transpiration (Eakin 1964). The headwater region, the his- toric range of the Moapa dace, is known as the Warm Springs area (Fig. 1). During our stud\' the area was used primariK' for agriculture, and up to 0.25 m Vs of river discharge was being diverted to irrigate alfalfa, barley, and pasture. Spring outflows had been channelized, and se\- eral were converted into irrigation ditches, some lined with concrete. Earthen tributan- channels had scant to thick riparian corridors of fan palm {Washingtonia filifera), tamarisk (Tamarisk sp.), ash trees {Frazinus sp.), and arrow weed (Pluchea sericea). Two nonnative fishes successfulK established in the Warm Springs area: mosquitofish {Ganihiisia affinis), present when Moapa dace were discovered in 1938 (Hubbs and Miller 1948), and shortfin moUy (Poecilia mexicana), introduced in the earlv 1960s (Hubbs and Deacon 1964). Besides Moapa dace and springfish, roundtail chub and speckled dace are the only native fishes occur- ring within the Warm Springs area, but they are rare and in greater abundance downstream (Cross 1976, Deacon and Bradley 1972). In 1979 the Moapa National \Vildlife Refuge (NW^R) was established in historic habitat at the southern edge of the Warm Springs area for the preservation and peipetuation of the Moapa dace (Fig. 1 ). The refuge stream originates from five small springs occurring in a radius of 70 m and having a cumulative discharge of abut 0.09 mVs (Fig. 2). Fan palms are the predominant riparian vegetation. In 1984 Moapa dace larx'ae and adults were reintroduced into the upper Refuge Stream, and by Januaiy 1986 there was a stable reproductive population of 120 adults (authors, unpublished data). Thev' were isolated by a 75-cm-high waterfall. Springfish were the only other fish present, and they were abundant. Materials and Methods RepR0DUCTI\'E BIOLOCY. — Among our objectives was to quantify' duration of the repro- ductive period and the season of peak laivae recruitment. To this end, a segment of the upper Refuge Steam system was snorkeled at 30- to 90-da\ intenals from Febnian" 1986 to |amiar\' 1989 and laivae were enumerated (Fig. 2). This is the area in which virtually all reproduction on the Moapa NWR occurred. Dace 7-15 mm TL were considered larvae. This range approximates the proto- to metalanae stages of the similar- sized speckled dace (Snyder 1981). Snorkeling enabled us to locate reproduction sites in the headwater Muddv River .system and to deter- mine the abundance and distribution of adult Moapa dace as well as to (juantifv hal^itat u.se for all life stages. Areas with lanae close to swim-up size (about 7 mm TL) were considered repro- duction sites. Fish used for food habit analysis and aging were also used to detemiine fecundit)^ H\BITAT use. — We defined habitat use in terms of stream depth and velocitv' at foraging sites and at suspected spawniing areas. Depth measurements included focal and total, while 218 Great Basin Naturalist [\blume 52 Colorado River 115 Fig. 1. Map showing relatioiisliip of the Miiddv to the Xiigin River and Lake Mead, Ne\'ada, ;uid relationship of the Warm Springs area to tlie Mnd(l\- liixer (helowV \\'ann Springs area or headwaters of the Muddv River showing tribntaiy streams to tlie upper Mnildv Ri\er and relationship ot the- Moapa National \\ildlile Rehige (above). 1992] MoAPA Dace 219 Upper Refuge Stream Fig. 2. Map of Moapa Nationd VMldlife Rcriigc: shaded site indicates the reaeli of the upper Refuge Streaiu where liUAae snorkel counts were made from Februan 19S6 to January 1989. \ elocih' nieasurenient.s included focal and mean water column, as prescribed b)' 13()\ee (1986). DissoKed oxxgen and temperature were also measured. Fish were located using mask and snorkel. A Marsh and McBiniex model 20 ID digital flow meter mounted on a calibrated rod was used to measure depth and velocitN-, and a Yellow Springs Instrument model 57 dissolved oxvgen meter for temperature and dissolved owgen. Sampling occurred from 1984 to 1986. Adult habitat was also defined b)' contrasting bod\- size with (juantitv of stream flow; it was our subjective evaluation tliat larger fish were inhabiting lariier water \ olumes. We tested this 220 Great Basin Naturalist [Volume 52 200 150 - _ 1 c 1 c 1 1 1 c 1 1 1 1 1 c 1, 1. 1 il i 1 1 1 L c -L 1 1 c 1 1 1 c c c 1 1 1 1 I c 1 T5 CO ^^ 0) E C LU (D CO _l o FMAMJ JASONDJ FMAMJ JASONDJ FMAMJ JASONDJ to i~- 'o 9J 00 CO CO CO o> en CT) O) Month / Year Fig. 3. Abundance of Moapa dace laivae from Februaiy 1986 to janiiaiy 1989 in tlie Muddy River system on the Moapa National Wildlife Refuge, Nevada. Bars represent a single dav's count for the month. NS indicates not sampled. h)^othesis in the summer of 1986 when samples of adults \\'ere minnow-trapped from the Muddy River, Muddy Spring Stream, Refuge Stream, and Apcar Stream and their length fre- quencies compared. Discharge for each stream was measured usino; standard U.S. Geological Survey methods (Rantz et al. 1982) near each fish sample. A one-way factorial ANOVA was used to test whether there was a significant difference between length frequency among fishes and different water volumes. Ace and GROVNTH. — The opercle bone was used for estimating age as described by Cassel- man (1974). Eight specimens, collected in summer 1985 and 1986, were aged. Flesh was scraped with a scalpel and the bone allowed to dry'. Glycerin was used to highlight the more transparent region of the bone, which was assumed to have the greatest calcium concen- tration and to have been formed in the winter when food is scarce. The more opaque region signifies greater concentration of protein asso- ciated with growth (Casselman 1974). Food habit— Food habit anaKses were made from 10 Moapa dace taken 9-1 1 Novem- ber 1984 from each of three uppc-r Muddv Riv(M- tributaries (Apcar, South Fork, and Muddv Spring). They were captured by seining and with unbailed minnow traps fished no longer than 10 minutes. Ranging from 42 to 71 mm FL, they were preserved in 10% formalin solution. Contents in the anterior third ol the gut were examined using a dissecting microscope and quantified by frequency of occiuTence (Windell 1971) and by percent composition (H)iies 1950). Abundance and distribution. — The abundance and distribution of adult Moapa dace (>4() mm FL) were determined by snor- keling the upper Muddy River svstem begin- ning from 200 m downstream of Warm Springs Road bridge (Fig. 1). Except for 1984, the sur- veys included 5.3 km of the upper Muddy River and 7.5 km of its spring- fed tributaries (Refuge Stream svstem, Apcar Stream, Muddv Spring, South Fork, and North Fork). In 1984 the survev area was the same except that only the upper 130 m of the Apcar Stream was snorkeled rather than its entire stream length. Snorkeling was conducted over periods of foiu" to six days when turbidit)' was low (between 1.4 and 5.0 NTU) because no agricultural return flows were entering the stream. Coimts were made 6-10 December 1984, 6-10 June 1986, and 16-22 September 1987. Each observer enumerated Moapa dace twice at three areas of relatively high concentrations (30-60 fish), and the range of results was then calculated. These sites were chosen because the greatest variation among obsei-vers was expected among them. For the three sites, variation was less than 15% in counts 1992] MoAPA Dacb: 221 1,000 800 - c/5 LU CD n E 13 600 400 - 200 - 30 - r ^= .93 n =23 D D^ /^ ■ /-"m y^ -^D D - f^ D D - □ 02^ 1 1 1 1 1 1 40 50 60 70 80 Fork Length (mm) 90 100 Fig. 4. Moapa dace fecundit)- iis a tuiictioii of fork length. between indmduals; thus, we consenathelv estimated a 15% \ariation in o\\\ population counts. Results and discussion Reproducti\e Biolog)' Moapa dace lanae were found vear-round, iudicating\ear- round reproduction. On the Moapa NW'R peak lanal reciiiitment was in spring, tlie low in autumn (Fig. 3). Fish at other reproduc- tive sites in the Warm Springs area exliibited this same general trend. Seasonal fluctuation in lanal recruitment was probabh" linked to a\ ailabilitv' of food. In the upper Mudd\ Ri\ er system the abundance of benthic and drifting invertebrates is much lower in winter than in spring (Scop- {)ettone, un]:)ubli,shed data). Naiman (1976) documented substantial seasonal fluctuation in primar)' producti\it\' in anothei" southwestern warm springs where production is lowest in winter; presumably most invertebrate popula- tion fluctuates with priman' production. Recenth' emerged lanae were found within 150 m of spring discharge over sandy silt bot- toms in temperatures of 30-32 C and dissoKed ox)gen of 3.8-7.3 mg/L. Whether spawning occurs only at these head\\'ater sites or is suc- cessful onl\- at these sites is unknown. Visual cues such as sexual dichromatism, pronounced male spawiiing tubercles, or o\ertly gra\id females were not readily apparent, and spawiiing was not observed during our stud\". Howexer, we indirectly identified and quantified spawning habitat. The presence of hundreds of proto- lanae in a concrete irrigation channel immediately downstream of the Baldwin springhead (Fig. 1) indicated that reproduction had taken place. Progenitors apparentlv came from the South Fork, entering Baldwin Spring outflow through a diversion channel (Fig. 1). The concrete irrigation channel had homoge- neous water depth and \elocit\', and substrate was sandv silt. Se\eral depressions in the sand were similar to "redds" described for longfin dace (Agcw/V/ clm/so'^aster; Minckle\' and Wil- lard 1971). Depth and \ elocity at the suspected redds were representative of the outflow chan- nel and similar to other suspected spawning areas in the Warm Springs area. Depth ranged from 15.0 to 19.0 cm, near-lx^d \elocities from 3.7 to 7.6 cm/sec, and mean water colunm veloc- it\- from 15.2 to 18.3 cm/sec. Similar to the longfin dace, which repro- duces during much of the year (Kepner 1982), eggs in the skein of Moapa dace were in differ- ent stages of development. All visible eggs were counted, but because they are intermittently deposited and develop throughout a gi\ en year, our counts do not represent absolute annual fecundity. How^ever, egg production increased with fish size (r = .93, n = 25; Fig. 4). Counts 999 Great Basin Naturalist [\^olnme 52 80 60 40 20 0 gso >»60 O O 40 3 0 Li. 80 60 40 20 0 80 60 40 20 0 ^80 O 60 c 0 40 S"20 III 0 80 60 40 20 0 Dace Adults ; n = 564 H,.. Dace Juvenile n = 148 I Dace Larvae n = 201 .■, ,, 80 - 60- 40 20 0 0 10 20 30 40 50 60 70 80 90 100110 Total Depth (cm) Dace Juvenile n = 148 ' ' * I L. Dace Larvae n = 201 -1 1 * * Dace Juvenile n = 147 Dace Larvae n = 199 0 10 20 30 40 50 60 70 80 90 100110 Focal Depth (cm) 0 10 20 30 40 50 60 70 Mean Water Column Velocity (cm/sec) 80 60 40 20 0 80 60 40 20 0 80 60 40 20 0 Dace Juvenile n = 147 i Dace Larvae n = 201 0 10 20 30 40 50 60 70 Focal Velocity (cm/sec) Fig. 5. Mean water coliiinn and loeal point xelocitics, total depth, and local point depth nsed l)\ Moapa daei' adn juveniles, and larvae in the upper Mudd\ Rixcr system (Warm Springs area), Ne\ada. UiS-l through liJSB. 1992] MoAPA Dace 223 Tabi.K 1. Fork IcMigth, sex, ;iiul cstiinatecl age of" eis^ht TaBI.K 2. Fckk\ items ingested In 2] Moapa dace b\' Moapa dace collected from the upper Miiddv Hi\ cr s\ stem. percent conn^xjsition ( H\iies 1950) and percent frequence Ne\ada. in 1985 and 19S6. Age was (Ictcnniind 1)\ the ol occnrrence (W'indell 1971). Nine odier guts examined opercle method. w tre empty. FL (nnn) Sex Collection date Food items Age 45 55 61 67 69 SO 90 Unknown 4/86 Unknown 7/86 Unknown 7/86 Female 4/86 Female 04/22/86 Unknown 10/09/85 Unknown 10/11/85 Female 10/08/85 0+ 1+ 1+ 2+ 2+ 3+ 3+ 4+ ranged from 60 in a 45-nini-FL indiviclnal to 772 ill a 9()-nini-FL dace. Eggs were just developing in a 41-nnn-FL female and were matnre in a 45-mm-FL fish, suggesting that females mature at lengths in this range. Habitat U.se Again, Moapa dace larvae were found exclu- sixely in the upper reaches of spring-fed tribu- taries, while juveniles occurred primarilv in tributaries but were more far-ranging. Adults were present in tributaries and in the main ri\er, with larger fish generalK' found in the larger water volumes. There were significant differ- ences in length frequencies among adults from different water \olumes {p < .006). In the MudcK Rixer, in a flow of about 0.50 m Vs, mean FI. was 73 mm (/] = 78, SD = 16 mm); Muddy Spring had a flow of 0.20 m Vs, and the mean FL was 64 mm (n = 72, SD = 14 mm); the Refuge Stream flowed at 0.17 m'/s, and mean FL was 56 mm (/; = 64, SD - 8 mm); the Apcar Stream llowed at 0.06 mVs, and mean FL was 51 mm (n = 89, SD = 5mm). Lar\ae occurredand fed in tlu^ mid- to uppc^" region of the column. They were found most frequentk' in zero water velocit\" ( Fig. 5). As size increased, individuals tended to occupy faster water and occur lower in the water column, juvenile Moapa dace occupied focal and mean water column velocities ranging from 0 to 46 cm/s. Adults were found in a wide range of water depths and velocities, but they tended to orient at the bottom in low to moderate current. Water column depth ranged from 15 to 113 cm and focal point depth from 9 to 107 cm. Mean water column \elocit)- ranged from 2 to 77 cm/s and focal point velocit)' from 0 to 55 cm/s. Water temperatures within adult habitats ranged from % composition % of occurrence Gasthopoda Tt/ronui clathnita 1.1 Olk;()(:iiaf.tk 27.0 AMI'IIII'ODA Hi/dlli'la aztcra 1.7 IlKMIITKHA Pclocoiis shoshoiw 4.5 HOMOITKIU Apiiiidac 9.0 Tkiciioitf.ha Dolophilodcs 5.1 Necfop.si/clie 4.5 LEPlDOn'F.HA Para'^i/ractis 4.5 COLEOPTKKA Steucluiis ralicla 1.1 Dijtiscidae (lan'ae) 9.0 DiPTElU Chlronomidae 4.5 Unidentified insect parts 3.3 Filamentous algae 18.5 N'ascniar plants 3.4 Detritus 2.8 4.8 23.8 9.5 4.8 4.8 9.5 9.5 9.5 4.8 4.8 4.8 9.5 42.3 9.5 14.3 27 to 32 C and dissoKed o.wgen from 3.5 to 8.4 mg/L. Age Crowth Annulus formation is t\picalh' associated with an annual period of slower growtli cau.sed bv seasonal changes in environmental condi- tions such as temperature or food resources (Tesch 1971). Although seasonal water temper- atures do not change sul)stantiall\ in the Warm Springs area, there is an apparent reduction of potential food during the winter (Scoppettone, unpublished data). We were unsuccessful in aging Moapa dace bv the scale method because scales were small, embedded, and extremely difficult to remove from live specimens. Also, einiroiinuMita! conditions in waters of the Warm Springs area were sufficientlv constant that aiinuli were not readilv apparent. Assmiied annuli on opercular bones were presumed to be associated with slow(^r growth dining the winter. Ages of the eight fish examined ranged from O-l- for a 43-mm-FL individual to 4+ for a 90-mm- FL female (Table 1). Food Habit Nine of 30 guts examined were emptv' and the remainder generalK contained few items, 224 Great Basin Naturalist [Volume 52 Table 3. Estimated number of Moapa dace adults in six tributan- streams in the Warm Springs area, Muddv Ri\er system, Nevada, 6-14 December 1984, 1.3-18 June 1986, iuid 16-22 September 1987. Stream December X'ariation June \'ariation September Variation name 1984 in count 1986 in count 1987 in coimt Muddy River 475 ±71 1230 ±185 1165 ±175 Refuge System 370 ±56 406 ±61 806 ±121 Apcar 200 ±30 565 ±85 475 ±72 South Fork 300 ±45 185 ±28 100 ±15 Nortli Fork 15 ±2 30 ±5 60 ±9 Muddv Spring 1450 ±218 160 ±24 200 ±30 Total 2810 ±422 2581 ±387 2806 ±421 "Onh till- iippi-r loO in of stiva but what had been consumed indicated Moapa dace to be omnivorous tending toward caniiv- ory; 75% by composition was invertebrates while 25% was plant material and detritus (Table 2). Among 21 dace guts, oligochaetes represented the largest \'ohune (27.0%) of food- stuffs consumed, followed by filamentous algae (18.5%). In terms of frequency of occurrence filamentous algae occurred in 42.3% of the guts while oligochaetes were in 23.8%. The stmcture of the pharyngeal teeth also suggests an omniv- orous diet; they are strongly hooked but ha\e a well-developed grinding surface (La Rivers 1962). The presence of detritus and gastropods indicates at least some foramne; from the ben- thos, and we obsened fish in the field occasion- ally pecking at substrate. However, the greatest time in foraging is expended on drift feeding (authors, unpublished data), although our data set does not strongh' support this obsenation. Abundance and 13istribution Moapa dace were more widespread and numerous than had been previously rej)orted (Ono et al. 1984); they were in five headwater tributaries and the upper Muddy River to about 100 m downstream from the Warm Springs Road bridge (Fig. 2). Numbers ranged from about 2600 in 1986 to 2800 in 1984 and 1987. The numerical distribution for the three years suggests movement by the adult population (Ttible 3). In f984 the Muddy Spring stream supported about 50% of the population (1450 adults), with only ]6%> (450 adults) foimd in the river In June 1986 we could account for only 7% of the population in the Muddy Spring stream, while almost 50% of the total was in the river. In 1987 the mainstream river again supported most adult Moapa dace (1200). The distribution of adult Moapa dace was patchy and clumped. For example, during the snorkel suive)' in summer 1986, 79% of the observed dace in the main stem Muddy River were in groups of 10 or more, and 37% were in groups of 30 or more. In tributaries, groups were generally smaller, with 52% of the adults in groups of 10 or more and only 13% in groups of 30 or more. Conclusion Moapa dace are dependent upon the link between the upper ri\'er and its tributaries. The main stem river typically harbors the largest, and presumably the longest-lived, and most fecund fish; yet tributaries are important for reproduction and as lanae and juvenile nurser)^ habitat. Age and growth information suggests that three years is the mean age of fish in the river and that adults in smaller tributaries are one to two vears old. Although the Moapa dace population is more widespread and abundant than previously beliexed, its existence remains in jeopardy. Widespread movement and obligator' spawTi- ing near warm water spring discharge suggest that species survival depends on access to the entire headwater Mudd\' River svstem (Warm Springs area), river and tributaries alike. Everv effort should be made to presene all of its remaining habitat. Ac: K N OW L E D C; M E N TS William Burger and Dana Winkleman assisted in snorkel surveys, and Michael Parker and Nadine Kanim assisted in estimating fish populations. Peter Rissler helped to determine habitat use. Michael Parker conducted gut iuialv- sis. Glen Clemmer, Randy McNatt, and Tom Strekal reviewed the manuscript. Linda Hallock 1992] MOAPA Dace 225 ln'Iped with editing and Steplianic Byers with graphics. Literature cited R()\i:i:. K. D. iy- 101: 408-419. Eakin T. E. 1964. Ground-water appraisal of Coyote Springs iuid Kiuie Spring \'allevs and Mnckh' River Springs Area, Lincoln and Clark counties, Nevada. Nevada Department of Conseivation and Natural Resources, Ground-Water Resources — Reconnais- sance Series. Report 25. Garside. L.J. .and J. H. Schillinc: 1979. Thermal waters of Nevada. Nevada Bureau of Mines and Geolog\-, Bulletin 91. Mackav School of Mines, Universitv of Nevada, Reno. 163 pp. Harrington. M. R. 19.30. Archaeological e.xploration in southern Nevada. Southwest Museum Papers No. 4. Reprinted in 1970. 126 pp. IIlbbs, C, iind J. E. Deacon 1964. Additional introduc- tions of tropical fishes into southern Nevada. South- western Naturalist 9: 249-251. HuBli.s, C;. L.. and R. \\. Miller. 1948. Two new relict genera o( c\prinid iislies from Nevada. University o( Michigan Musemn of Zoology Occasional Papers 507: 1-30. ' Hynes. H. B. N. 1950. The food of freshwater sticklebacks {Gastewsteus aculeatus and Pijgpsteiis puiiii(iitii>)i. predictive models. Texas, ivateifoiel. Biologists have used variotis indices for assessing waterfowl nutritional status. Initially, only body mass was used (Hanson 1962, Folk et al. 1966, Street 1975, Flickinger and Bolen 1979), but later stmctural variables were incor- porated to adjust for individual size differences (Oven and Cook 1977, Bailey 1979, Wishart 1979). Ringelnian and Szvmczak (1985) and Johnson et al. (1985) re\"iewed a\ian condition indices and noted the value of an accurate index of lipids in migratoiy^ bird management. These studies noted that scaling moiphological \ari- ables with body mass provided tiseful indices to avian body condition. Northern Pintails {Anas aciifa)M-e one of the most widespread waterfowl species in North America (Bellrose 1980), but recently their pop- ulations have declined, making them a species of special concern (Smith et al. 1991). Our objectives were to pro\ide an ecjuation to pre- dict total carcass fat (b()d>- condition) of North- ern Pintails and to test that index on an independent data set. The auatonn'cal \ariables tested are suitable for field studies. Study Area The stud\ was conducted in the Southern High Plains (SUP) of Texas, an 82,88()-km- area that is one of the most intensixel)- cultivated regions in the Western Hemisphere (Bolen et al. 1989). Twents' thousand pla\as are present in the SHP providing winter habitat for waterfowl (Haukos and Smith 1992). At least one-third (>300,000) of the Northern Pintails wintering in the Central FK'w^ay wdnter on the SHP (Bellrose 1980). Methods Northern Pintails were collected using deco\'s and b)' jtmip-shooting on plavas and associated tailwater pits in the SHP from Octo- ber through March of 1984-85 and 1985-86. Tarsal length (measured from the junction of the tibiotarsus and tarsometatarsus to the point of articulation bet^veen the tarsometatarsus and middle toe, 0.01 mm), flattened wnng chord (measured from the insertion of the ahila to the tip of the tenth priman', 0.1 cm), and total body length (measured from the tip of the bill to the end of the p\'gost\le, thus avoiding complica- tions due to tail feather growth, 0.1 cm) were recorded for each bird. During 1985-86 an additional wing measurement was recorded from the insertion of the alula to the tip of the ninth priman' because the ninth primary maybe slightK- longer than the tenth. Birds were ])lucked and frozen. Ingesta and intestinal contents were remoxed in the laboratoiy. Birds then were ^ Department of Range and Wildlife Management, Texas Tecli Ui\iversi(\ . I .iilihoek. Texas T9K)9. -Box 464, Eldora, Iowa .50627. 226 1992] PlNTAII,C:()\'niTK)\ MODKLS 00' TaHI.K 1. X'arialile.s u.st'd in prcdictixc models ol IxxK condition lor Xortlicrn TiiitaiLs [Anas aciitd} on tlie Soiitlicrn IIi .05). A predictive model for fat was generated ff)r each sex using total bodv length (TOTAL), wing length (WING), tarsal length (TARSAL), and bocK mass (MASS) as cxplanaton- \ariables. In model 1 , regression coefhcients of cxpian- atoiy variables between sexes w(m-(> iu)t different (P > .05). A predictixe e(juati()n ap[)licable to I)oth .sexes was therefore constnicted which included a dunun\- xariable for sex (DSFX) as well as stnictuial \ariables. Th(^ second model was constnictcnl follow- ing John.son et al. (1985); a Lipid Index was dehncd: Lipid Index = Fat / FFDM. Fat-free dn' mass is included to correct for size tlifferences between indi\iduals. Lipid Index was transformed to: CI = log (Lipid Index + 1) because the structural measurements are allo- nietric and because logarithms can be used to linearize ratios (Johnson et al. 1985). The con- stant 1 was added to smooth tlie function. CI can be simplified to: CI = log(DM/FFDM) because DM = Fat + FFDM. Log FFDM was modeled as a function of the logarithms of structural variables (LTOTAL, LWING, and LTARSAL) and log DM as a hmc- tion of these plus the logarithm of bodv mass (LMASS) (Johnson etal. 1985). Unlike Mallards {Anasplatyrhynchos; Ringelman and Szxniczak 1985) and Canada Geese {Brantn canadensis; Ra\'eling 1979), water content of wintering Northern Pintails fluctuated widel\- (Smith and Sheeley 1993). Therefore, we did not test fat- free mass as an index to structural size (Ringel- man and Sz)'mczak 1985). Johnson et al. (1985) used k)garithms of structural \ariables to model logarithms of car- cass fat mass (log fat). A separate equation was estimated for each age/sex group (model 3) using dummv \ariables for age (DACE) and sex (DSEX) because regression coefficients for explanaton \ariables differed (P < .05) among these four groups. Predictixe equations were \alidated on a data set of 40 randomlv selected pintails not inchuknl in the generation of models. Percent- ages of each age/sex class of pintails in the inde- pendent sample were consistent with their occurrence in the sample collection. Pn^liction (MTor (PF) was calculated as an additional test of model jx'riormance. PE is defined as: PE = .Measured \' - Predicted Y, where Y is the dependent \ariable. Mean PE is an axerage \alue for all members of the \alida- tiou data set. Finallv, predicted fat, CI, and log fat wen^ correlated with Lipid Index in the \ alidation data. 228 Great Basin Naturalist [Volume 52 T.\BLE 2. Regression equations and associated statistics tor predicting carcass fat (model 1) content (g) in Northern Pintiiils (Anas acuta) collected on the Soudiem High Plains of'Texas, October-Mtuch 198-1— S6. r' Exjilanatory variables Equation Intercept MASS WING TOTAL DSEX 1.1 .779 P;xrameter estimate 191.854 0.560 -13.386 -4.136 _ (Male; n = 198) SE — 0.022 3.894 1.901 — \'ariance inflation factor — 1.181 1.231 1.221 — Piuti;il R- — 0.741 0.013 0.005 — 1.2 .711 Parameter estimate 145.570 0.570 -9.516 -4.953 — (Female; »i = 118) SE — 0.035 5.561 2.994 — Variance inflation factor — 1.125 1.212 1.174 — PartiJ R- — 0.691 0.007 o.oor — 1.3 .757 Parameter estimate 190.494 0.563 -12.068 -4.409 -22.513 (ComJDined; tt = 316) SE — 0.018 3.178 1.600 10.536 Variance inflation factor — 1.492 3.164 6.842 5.987 Partial R' — 0.726 0.011 0.006 0.004 •'Not .significant (P > .0.5). T.\BLE 3. Regression equations and associated statistics for predicting Condition Index (model 2) in Nortliern Pintails (Anas acuta) collected on the Southern High Plains of Te.xas, October-March 1984—86. r2 Expl anatory' v txriables Equation Intercept LMASS LWING LTOTAL DSEX 2.1 .673 Parameter estimate —0.816 1.371 -1.025 -0.909 _ (Male;;) = 198) SE — 0.069 0..343 0.312 — Vari;uice inflation factor — 1.190 1.233 1.229 — Partid R- — 0.656 0.015 0.014 — 2.2 .599 Parameter estimate —0.725 1.316 -1.179 -0.710 — (Female;/) = 118) SE — 0.101 0.512 0.486 — Variance inflation factor — 1.123 1.206 1.176 — Partiiil R~ — 0.595 0.019 0.008 — 2.3 .657 P;u"ameter estimate —0.761 1.350 -1.080 -0.834 -0.041 (Combined; n = 316) SE — 0.057 0.286 0.264 0.016 Varimice inflation factor — 1.496 3.207 7.035 6.141 P;utiiil R- — 0.610 0.016 0.011 0.007 Stepwise multiple regression (iiiiLximum R' improvement technique) was used to generate and test all models (SAS Institute, Inc. 1985). Variables were eliminated that did not contrib- ute significantly (F < .05) to a model. Partial R- values were calculated for each variable in a model. A sum of scjuares (Ty|:)e II) for each model variable was divided by the total sum of squares in the model. A partial R- value for a given variable represents the uni(|ue contribu- tion of that variable when all other \ariables are already present in the model. Partial H" values are not additive, and, therefore, their sum will not equal the total model K~. Differences in variation accounted for by ninth \ersus tenth primar\- length were evaluated using the K" pro- cedure (SAS Institute, Inc. 1985). Results In model 1 (Table 2) bodv mass ex|:)lained a major portion of \ariation in carcass fat content in males (equation 1.1) and females (equation 1.2). Total length did not account for a signifi- cant (P > .05) portion of variation in fat content for females as it did males. Based on low vari- ance inflation factors (\TF), regression coeffi- cient estimates for each sex were stable. When sexes were combined through use of a dummy xariable (equation 1.3), the \TF for TOTAL and DSEX were relatixeK' high; this is largelv attrib- utable to the hitrh correlation between length and sex of bird (point biserial correlation coeffi- cient ecjual to 0.91). LTOTAL, LWING, and LTARSAL ex- plained variation in log FFDM. For modeling. 1992] Pintail Condition Models 229 Table 4. Regression equations and associated statistics for predicting log carcass fat (model 3) in Nortlieni Pintails (Anas acuta) collected on the Southern High Plains of Texas, October-March 19S4-86. Explanator)' variables Equation Intercept LMASS LWING 3.1 .727 (Adult male; /) = 140) 3.2 .693 (Adult female; it = 69) 3.3 .722 ( |u\eiiile male; ii = .58) 3.4 .745 (Ju\enile female; n = 49) Parameter estimate —3.410 SE — N'iiriance inflation factor — Partial R- — Parameter estimate — 1 .61 1 SE — \'iU"iance inflation factor — Partial R- — Parameter estimate —11.066 SE — Vtiriance inflation factor — Partial R- — Parameter estimate —.5.444 SE — \'ariance inflation factor — Partial fi" — 3.412 -3.209 0.182 0.993 1.156 1.156 0.697 0.021 3.687 -4.998 0.303 1.472 1.034 1.034 0.687 0.054 5.028 -1.223 0.422 2.009 1.015 1.015 0.719 ().()()2 3.968 -2.834 0.348 1.844 1.109 1.109 0.720 0.013 Table 5. Coefflcients of determination (R'} and predic- tive error estimates from the xiilidadon (n = 40) of predic- ti\e equations to measured \ariables and Lipid Index for wintering Northern Pintails (Anas acuta) on the Southtni Iliiih Plains of Texas, October-March 1984-86. Mean prediction'' Lipid Index Equation R- error (± SE) R- 1.1 Mid 1.2 .785 -9.921 ± 5.850'' .662 (fat) 6.16% 1.3 .765 -9.043 ± 5.853 .659 (fat) 6.24% 2.1 and 2.2 .697 -0.0192 ± 0.0091 ,671 (Condition 1 Index' I 7.87% 2.3 .7(X) -0.019 ± 0.0()92 .675 (Condition ] [ndexl 1 7.79% 3.1-3.4 .7.33 -0.050 ± 0.()()()9 .634 (log fat) 2.41% ■"Prediction error expressed ;is a percentage of the mean in the validation data set. Negative prediction error iiuhcates o\erestimation of the true \alue. log DM, LMASS, LWING, and DSEX were significant (F < .05). TlnLs, CI was modeled with LTOTAL, LWING, LTARSAL, and LMASS for sexes separately and combined (Table 3). As in model 1, regression coefficient estimates were stable in equations 2. 1 and 2.2; when se.xes were combined, mnlticollinearitv betsveen TOTAL and DSEX resulted in relati\cly high MFs for these variables. Age and sex effects were significant when log fat was regressed on the same e.xplanaton' \ari- ables used in model 2. Furthermore, the struc- tural \ariables LMASS and LWING were the onlv variables that contributed siguilicantK (P < .05), but they were not homogeneous (F < .05) between age/sex groups. Therefore, four equations were estimated (Table 4). DAGE explained variation in log fat but not CI. Given other model variables, bodv mass (MASS and LMASS) consistentlv accounted for the largest portion of variation in carcass fat (Table 2), CI (Table 3), and log fat (Tiible 4) of wintering Northern Pintails. Wing length (WING and LWING) explained 1-5% of the variation in carcass fat, log fat, and (>I when other variables were itlready in the models. TARSAL did not contribute to any model. Vari- ation accounted for b\' ninth and tenth pri man- lengths always differed by less than 1%. Conse- quently, ninth priman' length was not tested in any model. In the \alidation data set all models accounted for 69% or more of \ariation in car- ca.ss fat mass, (]I, and log fat (Table 5). All models explained less than 70% of the xariation in Lipid Index for \ alidation data-set birds. Bias in all models was relatively low and negative. Predictive e(|uations overestimated fat mass, CI, and log fat of \ alidation data-set pintails. DISCUSSION A useful condition index will sa\e fimds b\ eliminating the need for expensive laboraton analyses and will lessen the need to sacrifice birds for direct nutrient anaKses. The problems 230 Great Basin Naturalist [Volume 52 associated with using body mass alone as an index to condition of migratory birds have been noted (Bailev 1979, Wishart 1979, Iverson and Volis 1982. Johnson et al. 1985). Because indi- viduals \aiy in stnictural size, bod\' mass will reflect that \ariabilitA' in muscle and bone, in addition to variation in lipids. Models have been dexeloped that predict fat content in waterfowl, but these require sacritice and dissection of the bird (Woodall 1978, Chap- pell and Titman 1983, Thomas et al. 1983, Whvte and Bolen 1984). These equations may incorporate skin (subcutaneous), abdominal (omental), and/or intestinal (visceral) fat mass, and often account for most of the variation in total body-fat content. Our study was designed to develop models using explanatoiy variables that could be applied to live as well as dead pintails. Miller (1989) developed regression models to predict carcass fat on live pintails from Sac- ramento Vallev, California, but cautioned against their use outside that region. Our regres- sion models for carcass fat provided better esti- mates of fat (K" > .71) for live pintails than those developed for California birds IR' < .66). How- ever, similar to Millers (1989) studv, bodv mass alone accounted for most of the variation (R' > .69) in pintail carcass fat. The possibility of a condition bias among water-fowl captm-ed in baited traps versus the general population has been addressed (Weatherhead and Ankney 1984, 1985, Buniham and Nichols 1985). Hypothetically, birds in poor condition may be hungrier, less wary, and more likely to enter a trap contiiining food. Condition models could be used to test for evidence of a body-condition bias, given that samples of pintails captured both in baited traps and bv presumably less-biased methods (e.g., net gun) are available. Models could be u.sed to test for annual variation in bodv condition and for chans;es in condition across the winter. Ringelman and Szymczak (1985) demonstrated the potential of condition indices in determining spatial differ- ences in body condition and the preferabilitv of condition indices to use of body mass alone. Heppetal. (1986) also used condition indic-esto docmnent a po.sitive relationship betAxcen con- dition and sun ival in mallards. The.se pintail condition models should be useful to waterfowl biologists. However, models should be verified when used outsick^ the eeo- graphical range in which they were developed. For comparisons between age and sex classes we encourage use of model 3. Research also may refjuire knowledge of absolute fat content. Importance of accuracy and precision will affect model selection. Care should be exercised to restrict model use to winter when changes in bod)' mass primarily reflect fluctuations in fat, not fat-free diy mass (i.e., protein and mineral fractions). Acknowledgments We offer our thanks to A. R Leif, CD. Olavv/sky, D. G. Cook, R J. Grissom, and R N. Gray for field assistance. E. G. Bolen, L. D. Vangilder, D. H. fohnson, and C. B. Ramsey provided comments on the manuscript. The project was supported by the Caesar Kleberg Foundation for WildHfe Consen'ation and the Texas State Line Item for Noxious Brush and Weed Control. This is manu,scriptT-9-488 of the College of Agricultin-al Sciences, Texas Tech Universitv'. LiTER.\TURE Cited Baii.kv, R. O. 1979. Methods of estiniatiujj; total lipid con- tfiit in the Redhead Duck (Aythi/ti (nucrianui) and an ex'aluation of condition indices. Canadian lonrnal of Zoologv 57: LS3()-LS33. Bii.LHosE, F. C. 19(S0. Ducks, geese tuid swans of North America. 3rd ed. Stac^iole Books, Harrisburg, Penn- SN'Kania. Bolen, E. C, L. M. Smith, and II. L. Schhamm 19S9. Plava lakes: prairie wetlands of the Southern High Plains. BioScience 39: 6L5-623. BuRNUAM, K. p., and J. D. Nichols. 1985. On eoncbtion bias and liand-recoxcn- data from large-scale waterfowl bantling programs. Wildlife Societv Bulletin 13: 345- :349. CiiAPl'KLL. W. A,, and R. D. Titman 1983. EsHmating reser\'e lipids in Greater Scaup (Aijthijd iiwiihi) and Lesser Scaup (Ai/thi/a affiuis). C'anadian |onrnal oi Zoologv 61: 3.5-38. Flickincek, E. L., and E. G. Bolen. 1979. Weights of Lesser Snow Geese taken on their winter range. Jour- nal of Wildlife Management 43: ,531-533. Folk C., K. Hudec. and J. TOUFAH 1966. The weight of the Mallard {Anas plati/rlnjiichos) and its changes in the course of the \ear Zoologx List\ 15: 249-260. Hanson 11. C. 1962. The dviiamics of condition factors in Canada (ieese and their relation to seasonal stresses. Arctic Institute North .America Technical Paper No. 12. Fairbanks, Alaska. ilMKds D. A., ;uid L. M. Snutii 1992. Ecolog\- of plava lakes. In: Waterfowl management handbook. LI.S. Fish and Wildlife Ser\ice Leaflet 13.3.7. ill IT (;. R., R. J. Bloiim. R. F Reynolds J. F Hines. anti |. D. Nichols 1986. Physiological conchtion of antnnm-banded Mallards ;uid its relationship to hunting 1992] PiN'IAII, CoxniTIOX MODKLS 231 \iilii('ral)ilit\. |()iinial ol \\ ildlifc Maiia<4ciiH'iit 30: 177- ].S3. 1\ KHSON. C. C;., and P. A. N'oiis, |ii. 19S2. Kstimatiii'^ lipid content oi Sandliill (francs Ironi anatomical nicasurc- nicnts. Jonrnal of Wildlife Management 46: 478—48.). JOHNSON 1). II.. (;. L. Khai'I K, J. Hkinkckk, and 1). C. |oiilM; 1985. .\i\ e\alnati()n of condition indices for birds. |onrnal of \\ ildlifc .Management 49: 569-.575. Miil.KK. M. H. 1989. Estimating carca.ss fat and protein in Xoftlieni Pintail.s during tlie nonhreeding season, journal olWildlif'e Management 53: 123-129. OuKN. .\I., and W. A. Cook 1977. N'aiiations in hocK weight, wing lengtli and condition of Milliards (Aims pl(itijrlujncli()s)im(] tlic-ir relationsliip to en\iromneutal changes. Journal of ZoologN' 183: 377-395. Hw Ei.lNC. D. G. 1979. Tlie annua! cvcle of hodv composi- tion of Canada Geese witli special reference to control of reproduction. .\nk 96: 234-252. Hi\(:i:i \i \N ]. K.. and M. R. Szymcz.ak. 1985. A ph\-.sio- logical condition index for wintering Mallards, [ournal of Wildlife Management 49: 564-.568. S.AS IN-STITLTE. I\C 1985. SAS user's guide: statistics. Version 5 edition. SAS Institute. Inc.. Can. North Carolina. Smith C.W., F. A. John son |. B. Boktxer. J. P. Bl,\di;n. and P. D. Kkvwood 1991. Trends in chick breeding populations. U.S. Fish and Wildlife Senice .Administrati\e Report. Laurel, Mar\'land. SNirrii. F. M.. and D. G. SllKKl.KV. 1993.' Factors affectine i-ouditioii of .\ortlu-rn Pintails in the Soulheru High Plains. Jonrnal of Wildlife Management 57. In press. Sii!i:i;t. M. 1975. Seasonal changes in the diet, bodv weight and condition of fledged Mallards in eastern Enghuul. International (>ongre.ss of Came Biologists 7: 339-347. TiioM.AS. \'. (;., S. K. M.MNCUY, and J. P. Phk.\ i-.TT. 1983. Predicting fat content of geese from abdominal fat weight, journal of Wildlife Management 47: 1115- 1119. \\i:\riii:niii;\i) P. J., and C:. I). Ankni-:v. 1984. A critical assiunption of band-reco\ en models mav often be \iolated. Wildlife Society Bulletin 12: 198-199. . 1985. (Condition bias and band recoven data: a repK to Bnrnham anil \ic hols. Wildlife Societv Bulle- tin 13:349-351. \\ iivri: R. J., and E. C. Boi.KN. 1984. \ariation in winter tat de-pots and condition indices of Mallards. |onrTial of Wildlife Management 48: 1370-1373. WisiiAHf. R. A, 1979. Indices of .structural size and condi- tion of .American Wigeon (Aims aiiwricaiia). Canadian Jonrnal of Zoolog\- 57: 2369-2374. Wooii.M,!., R F. 1978. Omental fat: a condition index for Red-billed Teal, [onmal of \\'ildlife Management 42: 18.8-190. Received 1 fuiic /.9.9/ AreepU-d 22'}\nie IW2 Great Basil) Natunilist 52(3). pp. 232-236 EVALUATION OF ROAD TRACK SURVEYS FOR COUGARS (FELIS CONCOLOR) \\ alter D. \ an Sickle aiul Frederick Ct. Lindzev .'Kli.sTlucr — Road track sui"\'e\s were a poor index of eoutjar ileiisitA in .sontlieni LUiili. The weak rekitionship we iound betsveen track-finding frequency and coug;u" den.sit}' imdouhtedK' resulted in piut from the fact that aviiilable roads do not sample properK' from the nonuniformlv distributed cougar population. Howe\er, the significantly positi\e relationship ir" = .73) we found between track-finding fre(jueuc\ and number of cougar home langes crossing the sur\('\ load suggested the technique may be of use in monitoring cougar populations where road abundance and location allow tlie population to bv sampled properK. The amount of variance in track-finding frequency unexplained 1)\ number of iiome r;uiges o\erlapping suiACN roads indicates the index ma\ be useful in demonstrating onl\- relati\'el\' large changes in cougar population size. Kci/ uiirds: cDiti^cir. Felis coneolor. truck .s»rrr//. l^tali. Sign left by animals ha.s been connnonly u.sed b\- wildlife managers to make inferences about population characteristics (Neff 1968, Lintlzevet al. 1977, Novak 1977). This approach is appealing becan.se it .seldom recjuires special- ized equipment and is usually nnich less costlv than other, more intensive techni(jues. The approach requires, however, that the relation- ship between sign and the population character- istic of interest (e.g., size, composition) be understood. Track counts have been used to indicate cougar (Fclis co)}color) abundance or change in abundance, but population estimates were seldom available to evaluate the validitv of these indices (Koford 1978, Shaw 1979, Fitzhugh and Smallwood 1988). \'an Dyke et al. (1986)', how- e\er, conducted road track sunews in an area of known cougar densit\ and found a weak rela- tionship (/■" = .18) between track-finding fre- (jueucv and densitv. Because of the potential value ol this techni(}ue to agencies charged with management of cougars, our objectixe was to test again the relationship between track-find- ing f re(|U(Micy and cougar densit\ follow iug [)ro- cedures of Van l>ke et al. (1986). AdditionalK. we examined the influence cougar distribution patterns, as measured b\ cougar home ranges, had on track-finding lre<|U(mc\. Study Aiuv\ The Bonlder-Escalante stud\' area comprises 4500 knr of Garfield and Kane counties in south central Utah. Boulder, Escalante, and Canaan moimtains dominate the area topographicallw and elevation ranges from 1350 m to 3355 m. Hot, dry' weather is characteristic of )nne and July, with rains beginning in August and contin- uing through September. Annual precipitatit)n ranges from 18 cm at low elexations to 60 cm at high elevations; axerage temperatures for Escalante in januan and juK' are -2.8 C and 24.5 C, respectixcK" (U.S. Department of Com- merce 1979). Desert grass and shrub communities domi- nate the \egetation with a sparse o\"erstoi^' of piu\()n pine {Finns cdiilis) and juniper ijunipcrus (isti'Dspcniui) between 1350 m and 1800 m. Dense pinxon-juniper stands with a sagebmsh {Aiicinisid tridciitatti) underston' dominate the xegetation between 1800 m and 2400 m. Ponderosa pine {Finns poiidcro.sa) and oakbrush {Qucrciis i(lcs). WyoiningCoi.iu-ratiw Fisli unci Wildlife- Hi-sr.ucli I'liil. I5i)\ .-^Kifi, Uiiivcrsitv St.itiiiii. 1„ . \\voiiinii;.S207r O-T,--) 19921 CoucarThack Slknkv 233 a\id w liitc lir (Al)i('s concolor^ occur ahoxc 2700 111. Hi\ er camons transxcrse the area with asso- ciated \e shoulder ol the road xxas dragged Once ;ill tour Avvds had be(^n surxexed, xx'e returned to the first aica, randomly selected different 16-km suncx routes for each area and l)egan the se(juence again. Sunex ed roads xxere not eligible for resampling until all dirt roads xxithin an area had bcx'u sampk'd once. For analxses. each 16-km section ot road xxas di\ ided into segments xai"xing in length from 1 to 10 km depending on the numlx^r of home 234 Cheat Basin Natlhalist [\i)l r2=0.73 df=3 P = 0.066 0 0.005 007 0075 0.02 TRACK SETS PER KILOMETER SURVEYED Fig. 1. Relationship behveen cougiu' track sets per kilo- meter and cougars with home rmiges overlapping tlie snr\i\ road on the Boulder-Escakuite stuch' area, lltah, 19SS. ranges o\erlapping the segment. Each segment tlien had a home range oveHap \'ahie (2-7) and was assigned one of the ionr densitv xahies. We examined the relationship between traek sets found per km sunexed and the t\vo niea- sin"es of densit\"\\dth simple regression anaKsis. Road segments with the same home range o\ er- lap values were eombined to obtain km sur- veyed, as were road segments representing the same densities. Data points entered into the regression etjuations were the siun of traeks found in eaeh of the six home range overlap or four densitv categories divided bv the sum of km surveyed in the respective categories. We evaluated whether dragginti would improve suivev roads with a simple regression of pre-drag dust ratings against post-drag rat- ings. Data from both road track sune\\s were combined to increase sample size, and regres- sion slopes were tested against 1. The number of track sets found on dragged and undragged roads was also compared b\' dividing the total luuiiber of track sets in each by the total km searched in each. Multiple regressiou analysis was used to examine the effect of rainfall and traffic on one-day, post-drag dust ratings. I're-drag dust ratings, rainfall, and traffic were the in(k^pen- dent variables considered. We used two indica- tor variables to code the three levels of rainfall and two to code the three levels of traffic. The three road surface categories related to increas- ing rainfall intensit)' were: unchanged, dimpled (individual raindrop impressions distinct), and deformed. Traffic categories were: no traffic, traffic on one-h;i]f the length of the road, and traffic on more than one-half the length. Results The systematic njad track siuAevs were con- (hicted Mav-june 1988. During this period 407 km of road v\'as surveyed and two track sets were found. One-hundred thiitv-five km (12 surveys) of road was sun'ev'ed in an area where 2-3 ranges overlapped the suney road, 146 km (13 sui"vev's) where 4-5 ranges overlapped, and 126 km (11 sunevs) where 6-7 ranges overlapped the survey road. Unequal survev numbers resulted from weather or ecjuipment problems precluding surveys being run. Each road (11.3 km) was sruveyed in three hoiu's, v\ith tv\'o areas being surveyed the first day and the third the next da\\ The two track sets were found on a road overlapped bv 4-5 cougar home ranges. Because of the small number of track sets found, these results were not regressed against either measure of densits'. Random-sv'stematic road track siu-veys were nni in Inly and August 1988. During this period 684 km v\as siu'veved and seven cougar track sets v\'ere found. Three hundred fiftv km (37 road segments) was located in an area of lovv- home-range/road overlap and 334 km (42 road segments) in high. The number of km searched per day was 16. We identified no relationship between den- sitv, as measured in cougars per km", and track finding frequency (r = .00, P - .886, n = 4). However, the relationship (Y = 2.23 + 197X, r = .73, P = .066, ROOT MSE = 1, /i = 5) betvyeen number of cougars knov\ni to have home ranges overlapping die road and track-finding frequency was positive (Fig. 1 ). Tlu^ data point associated v\ ith the home range ov erlap value of 7 was drop- ped because <20 km of road v\'as suneved. Results from both one-dav periods and three or more days were combined for these analvses. Because of the small number of track sets lound, we did not statisticalK evaluate the rela- tionship beh\'een track-tinding frequency and dust rating categories or dragged and undragged roads. We found a positive relation- ship between post-drag dust ratings (Y) and pre-drag ratings after one (AT) and three or more (X2) days (r = .54, Y = 6.05 + 0.875X1. P < .001, ROOT MSE = 10.4, n = 43) (r = .34, Y = 3.14 + 0.707X2, P < .01, ROOT MSE = 4.6, n = 20). However, we ftiiled to reject the null 1992] CorcAH Track SrH\i:Y 235 li\ potlicsis islopi' = 1 Hii both cases, iiidicatiiisj; that our iiictluKl ol road drasfs^iiiu; did little to iiiiproM' ttaekiiiij; inediuiii or that dust iatiu'j;s were uot sensitixe enough to detect changes in the tracking medium. Data associated with heaxA rainfall \\ t're omitted Irom these anaKses. Multiple regression anaKsis (onc^ da\ ) relating [)()st-drag dust ratings to pre-drag dust ratings, lain tall, and traffic Nielded a three-variable model that contained onl\- pre-drag dust ratings (A'l 1 and rainfall (X2, X3) as the independent \ ariables (r = .67, Y = 7.65 + 0.838X1 + 0.76X2 - 5.65X3, P < .000[X1], P < .583[X2], P < .001 [X3]. ROOT MSE = 9, /i = 43). Moderate rainfall had little effect on post-drag dust rat- ings. Howexer, heaxA' niintall resulting in road surlace deformit\" had a deleterious effect on post-drag dust ratings. The effect of traffic on post-drag dust ratings was not signiHcant(F> .05). location in determiiu'ni^ umuberof tracks found, use of index \alues to compare cougar density betx\eeu areas in tenuous. The probabilitx of existing road net\\'orks in t\\T) area.s sampling similarh' from tiu^ tA\'o po])ulations seems small. U.se of track suiacns to document cougar pres- ence is feasible, but again, the approach ulti- mateK relies on loads intersecting a cougar home range. IdealK; roads with suitable trackin*! surface o should be abundant, as in paits of the Northwest where logging is connnon, and located .so that the home range of each cougar would be inter- cepted. Even in an ideal situation, howe\(M\ the index maxpnne sensitixe onlv to relativeK' large clianges in cougai" [lopulation size. Twentx- sexen percent of the xariauce in number of tracks found xx-as unexplained bx' number of cougar hoiiu^ ranges ()xerlap[)ing sunex* roads. Discussion The ntilitx of road track sunex's for monitor- ing cougar abundance is limited bx' the generallx' ])()()r relationship betxveen cougar density and track-finding frequencx'. Both our results {>" - .00). although based on a small sample, and tho.se of\'an Dxke et al. (1986) {r = .18) inilicate a weak relationship bet\xeen cougar densit) and track-finding frequencx'. The strongest signifi- cant relationship found bx \'an Dyke et al. {r - .61 ) resulted from a nuiltiple regression model with track-finding frecjuencx' the dependent \ ariable and female densitx; good tracking con- ditions, aud proxiuiitx of cougars to sunex road the iud(q)endent \ariables. As the authors noted, hoxxexer. a biologist xvould sekUjin haxe kuoxxledge of cougar distribution in regard to sunex' roads. The poor relationship documented betxx'een track-finding frequencx and cougar densitx appears tlie n^snlt of sampling problems, largelx bexond the coutiol of the biologist. (Cougars an^ rarelx uuiloruiK distribut(nl (Hemkc^r et al. I9S4!. and axailable roads, the sampling sti'ata. are sekkim abundant enough or optimalK located to sample from a nonnniforui distribu- tion. .\xailable roads, for example, could fail to intercept anx' cougar home ranges or could be found ()ul\ in the areas occupied bx cougars, in both scenarios, the index (tracks found) could easilx proxe to be a poor measure of change in cougar numbers o\-er time in an area. Likexxise, because of the potential importance of road AcKNow i.i:i:)(;.\iENTS This research xvas fimded bv the Utali Dixi- sion of Wildlife Resources and administered bx' the \\\"oming and Utah Cooperatixe Fishen and Wildlife Research Units. We thank W. j. Bates for coordinating oiu" project thnigh the UDWR. H. J. Harioxx; R. A." Poxvell, L. L. McDonald, aiul D. G. Bonett rexiexved initial drafts of the manuscript. \\^e offer special thanks to C. S. .Mecham and M. (]. Mecham for field assistance and fimctioniug as houndsmen. LlTl'lHATlM^I-: ClTK.n .AcKKHMAN, H. H. 19S2. (^ouiiar pivdation and ecological energetics in sontliem Utiili. Unpublished masters tliesis, Utah State University, Logiui. 95 pp. FiTZHUcar E. L., and K. S. Smai.i.uood 198S. Teclnii(jue.s for monitoring monntmn lion population le\eLs. Pages 69-71 /■;/ H II Smith, ed.. Proceedings of the Third Moimtaiii I, ion Workshop, .\rizona Came and Fish Department. Ill Mkl-K T. v. 19S2. Pi )[)nlat ion characteristics and mo\e- ment patterns (jf cougars in southern Utah. Unpub- lished masters thesis. Utah State Unixersitv Logan. 66 pp. ill Aikii; T. P.. 1' (;. I,lMr/.l•,^ and B. B. Ac kkhnian 19S4. Population characteristics and moxement patterns of cougars in .southern Utdi. journal of Wildlife Manage- ment 48: 1275-12S4. KoiOlU). (J. B. 1978. The welfiueol the puma in (!aliloniia. Camixore I: 92-96. I.ixnzKY. F. C. S. K. Thompson and J. 1. nou(a:s 1977. Scent station index of black bear abundmice. Journal of Wildlife .Management 41: 151-1.53. .\kfk D. ). 1968. The pellet-group count technique for big game trend, census, and distribution: a re\iew. Joumal of Wildlife Manauement .32: .597-614. 236 C;reat Basin Naturalist [\oIiime52 NOXAK.M. 1977. Determining the a\erage size and coinpo- presence. |ounKiI (.rWildlifr .Management 50: 102- .sition of beaver familie.s. |()urnal of Wildlife Manage- 109. ment41: 751-754. U.S. Dhpahtmiat OF Conlmkiu:!'. 1979. CJimatokweal Sll.uv. II. C. 19,9 A monntam lion Held gnid<>. .Arizona data annual snmnian. Climatologieal Data Utdi Game and Fi.sli Department Special Report No. 9. 27 Sl( 1.3) pp. \\\ DvKK. F. G., R. II. Bkockk and II. G. Shaw 19S6. U.se ol road track connts a.s indices of monntain lion Received U) \oiemh ■ ■ IMl Accepted 16 April 1992 Great 13asiii .\atiir;Ji.st 52(3), pp. 237-244 LEAF AREA RATIOS FOR SELECTED RANGELAND PLANT SPECIES Mark A. Welt/,', Wilhcrt H. Blackhuni". and J. Hosier Sin laiitoii' AHSTKACr — Leaf area estimates are re([iiiretl In Indrolojiie, erosion, and 'j;ro\\ tli A ii'kl siniukition models and are important to the nnderstanding ol trtuispiration, interception, COo fixation, and tlie energ\ balance for native pkmt connnnnities. Leaf l)iomas.s (g) to leaf area (nim") linear regression relationships were e\alnated for 15 perennial grasses, 12 shruhs, .md 1 tree. The slope coefficient ((So) of the linear regression eqnation is a ratio of leaf area to leaf hiomass and is definetl as the leaf area ratio [LAR = one-sided leaf area (nim~)/()\en-dr\- leafweight (g)]. LAR represents (3(1 in each regression eqnation, where Y = P{|(X). Linear regression relationships lor leaf area were compnted (r~ = .84-.9S) for all 28 natixe nuige species after fnll leaf extension. Within-pkint estimates of leaf lU'ea for niesquitc iProsojns ^Idiidulosa Torn \Ar.<^hni(liiIosa [Torr.] Cockll.) or liinepricklviish (Zanthoxt/hnn fag^ara [L.\ Sarg.) were not significantK' different (P< .05). LARs for three of the shnibs and the tree were established at fonr different phenological stages. There were no significant differences {P < .05) in LARs for lime prickh- ash, niesqnite, and Texas persimmon {Diospijras texana Scheele) after fnll leaf extension dnring the growing season. The LAR relationship forTe.xas persimmon changed significantly after fnll leaf extension. LAR relationships for Texas colnbrina (Cohtbrina texemis [T & G.] Gray) changed in response to water stress. Kct/ tcanls: h'tij diva index, drought response. Icafhioiiiaw Eighh" percent of the world's rangeland is classified as arid or seniiarid (Branson et al. UJSl I. i.e.. precipitation is less than e\"apotrans- piratioii. Under these conditions water axail- al)ilit\' is tile most important en\ironniental factor controlling plant production and snni\ al t Brown 1977). E\apotranspiration (ET) is the major component of the water balance and is estimated to accomit for 96% of annnal precip- itation for rangeland ecos\stems (Branson et al. 1981, C^arlson et al. 1990), with surface rinioff accounting for most of the remaining 4% (Gifford 1975, Lauenroth and Sims 1976.' Carl- son et al. 1990). Ex'apotranspiration has Ixn^n irieasiired for selected rangeland plant coimnunities with Ksimcters and tlu^ Bow en ratio method (\\'ight 1971, Hanson 1976, C;av and Frit.schen 1979. Carlson etal. 1990). Estimates of ET for mnnea- sured rangeland plant connnmuties are usualK' simulated from hydrologic models (Lane et al. 1984, \\'ight 1986). For luclrologic simulation models to be biologicalK' meaningful, inipnned metliods of sinnilating exapotranspiration from rangeland plant connnnnities are needed. Two different approaclies are currently being used. One approach is to use a crop coefficic^nt (Kc) (W'ight 1986). Kc is defined as the ratio of actual exapotranspiration to e\apotranspiration when water is nonlimiting. This empirical method is extremeh' difficult to parameterize for range- lands because water is often limiting and esti- mates of transpiration are confounded h\ soil water exaporation (Wight and Hansen 1990). Thus, \Vight and Hansen (1990) reporied that Kc \alues were not transferable across range sites. The second method is based on leaf area inde.x (LAI) (Ritchie 1972). LAI is defined as the foliage area per unit land area (Watson 1947). The LAI method is uiore process-ba.sed than the Kc approach and has Ikhmi siiccesshdK used in se\eral rangeland Indrologic, erosion, and growtli/\ield sinnilation models (Wight and Skiles 1987, Lane and Nearing 1989, Arnold et al. 1990). A limitation in using natural Resource models, like the \\'ater Erosion Prediction Proj- ect (WTPP) (Lane and Nearing 1989), is in dexeloping L.\I c-oefficients for rangeland [)lants. LAI is difficult to measiu-e because of the drought-deciduous nature of certain shrubs, in wliicli sexcral c\cles of leal initiation and defo- liation occur within a single growing season (C;anskoi)p and Miller 1986) and seasonal .,USD,\. .Xgriciiltural Rp.search Senice. Southwest V\atersliecl Researcli Center. 2()()() F,;Lst Allen Road. Tucson. .Arizona 8.57194.596. "Northern" Plains Area Adniinistratne OITice. 2625 Redwing Road. Suite ^50. Fort Collins, Colorado 80.526. 231 23(S (;hkat Basin Naturalist [Volume 52 TaBI.K 1. DfSfriptioii of studv sites, raii^e sites, and soil series oC species exaliiated (or leaf area to leaf hioiiuiss relationsliips. Frost- .Mean i>p'r In 'c [)eriod Location Range site (mm) (days) Soil series Soil famiK T<)iiihstoii(\ AZ I,iine\ upland .■35(i 239 Stronghold ('oarse-loaiiiN, mixed thermic, Ustollic Calciorthid Meeker. CO (;Ia\('\ slopes 200 ISO Degater Clav, montmorillonitic, mesic, Tvpic Caniborthid Sidnev. MT Siltv .300 130 \ida Fine-loamv, rui.xed, T\pic Argboroll Chickaslia. OK Loani\ praiiie 927 200 (;rant Fine-silty. nii.xed, Udic .\rgiustoll Cliiekaslia. OK iM'oded prairie 927 200 Eroded C;rant Fine-siltv, niLxed, Udic Argiiistoll Ft. SiippK. OK Dnne .597 200 Pratt Sandy, mixed, thermic, Psammentic Haplustalf Wooilward. OK Shallow praii'ie 5S4 200 Oiiinlan Loam\-, mixed, thermic, shallow T\pic Ustochrept Alice. TX Fine sand\ loam 710 2S() Miguel Fine, niLxed, h\perthermic, Udic Palenstalf Soiiora, TX Shallow 009 240 Punes Fine-loam\-, mixed, thermic. T\pic Calciustoll cliaiiti;c.s ill leaf .size, shape, antl/or tliickues.s i.s with the leaf area ratio (LAR) method (Rad- re.siilt IVoni water, nutrient, and chemical ford 1967). LAR is defined as the ratio of leaf .stresses ((>utler et al. 1977, (>urtis and Luchli areaper unit weight ofplant material. The slope 19S7). Foliar surface area of irregular-shaped coefficient On) of the linear regression e(juatit)n tree leaxes has l)een estimated b\- coating the is a ratio of leaf area to leaf biomass and is Iea\es witli a monolayer of glass heads and mea- defined as the leaf area ratio [LAR = one-sided suring displacement (Thompson and Le\ton leaf area (nnn-)/oven-diy leaf weight (g)]. LAR 1971) and 1)\ estimating from photographs represents Po in eacli regres.sion equation, (Miller and Scliultz 1987). Miller et al. 0987) where Y = P(,(X). LAI can be calculated as the estimated total surface area of juniper foliage product of LAR and live biomass per unit area, from projected leafar(\i determined from a leaf Tlie objectixe of this study was to determine area meter. Miller et al. suggested this method LARs for selected rangeland species, underestimated leaf area by 10% diic to leaf owrlaj). Cregg (1992) reported that knif area MATERIALS AND METHODS could be satisfactoriK' (\stimate(l from leaf weight or xolume ior Juiiipcnts vir^iiiiaiia and The study area included nine range sites in J. .sco})til<>niiit. llowexcr. leafar(>a r(>lationships fUe states and was part of the USDA Water differed In crown position and seed source. Erosion Prediction Project (WEPP) (Table 1). Sapwood area, stem diameter, trec^ height. The dominant plants on each range site were canopy area, and canopy \()lume ha\e been exaluated. LARs for 15 grasses, 12^ shrubs, and correlated to total .shrub biomass and leaf bio- 1 tree were deyeloped (Table 2). Selected mass (Ludwiget al. 1975, Brown 1976. Ritten- rangeland .species were sampled once during house and Snexa 1977. Whi.senant and Burzlaff the sununcM- of 1987 near Tombstone, Arizona; 1978. Cianskopp and Miller 1986, Hughes etal. and in 1987 near Meeker, Cok)rado; Sidney, 1987). In contrast, onl\ a few studies ha\('esti- Montana; Chickaslia, Ft. Supply and Wood- mated leaf area and LAI for rangeland plant ward, Oklahoma; and Sonora, Texas, sites. Sea- communities ((;olf 1985, (;au.skopp and Miller sonal fluctuations in LAR for du'ee shrubs and 1986, and Ansley et al. 1992). oiu^ tree were exaluated near Alice, Texas, in An eftecti\(> method is needed to iinpro\e 1 985 and 1986. LAI estimates lor natural resource models. One Vov k^af area (k'termination grass leaf bioma.ss potential a[)pr()acli lor impnning LAI (>stimates from 10 raii(k)mK located ().25-nr (jnadrats was 19921 Ranc;ela\u Leaf Area K.vnu.s 239 TMii.!-; 2. Ixjcation of stucK' sites, sample dates, Iieitjlit class, iiniiiher of samples, and species exaliiated for leaf area to at liiomass relatiousliips. Height class (iii) Species Location Sample 0-11-2 2-3 3—4 >4 (ionimon name Scientific name date ihston Meeker, CO AZ Aucr. 1983 Au>i. 1983 An Jan. 1986 NA' Apr. 1986 2 2 2 2 Ma\- 1985 5 5 5 5 Aug. 1985 3 3 3 3 Nov. 1985 3 3 3 3 Jan. 1986 3 3 3 3 Apr. 1986 \la\- 1985 3 5 3 5 3 3 Aug. 1985 5 5 Nov. 1985 5 5 Jan. 1986 5 5 Apr. 1986 .\Ia\- 1985 5 5 5 5 .\ug. 1985 5 5 Nov-. 1985 5 5 Jan. 1986 NA A]K-. 1986 5 5 Soiiora, TX |niie 1987 10 June 1987 10 June 1987 10 Little l("af sumac Tarbusli Hrooiii snakeweed Creosotel)usli Desert /.iimia Mariola Shatiscale saltl)usli \\'\()ming big sagehnisli Needle-and-tl u'ead Western wheatgrass Indiangrass Big hluestem Little bluesteni Buffalograss Seribners dicliai 1 1 1 lel i 1 1 m Sand paspalnm Sand sagebrusli Tall dropseed Sand lo\egriiss Haii^v grama Sideoats grama I lonex mesiiuite Hliiis inicr()j)liijll(i Kngelm. Floiireiisia ccmiia DC. (Uiticrrczia sarotlirae (Pursh) Hritt. 6c Rusb\. Ijirrcd tridoitata (DC.) Coxille 'Aiimhi puiuila Cra\ hnihciiiiDu iiicanitm H.B.K. .\lri])lcx cotifeiiifolki (Torr. & Frem. ) Wats. Aiicinisia trklenlala sulwp. ut/(>ininri)i><^()n gcrardii Vitnuui Scliizaclii/hiiin scoparium (Mich.x.) Nasli Biichlof (Idcti/loklcs (Nutt.) Fngelm. niclunilhcliitm olif^osaiUlies (Scluilt.) (aiikl \ar. scrihiicrianuin (Niish) Could I'dspaliim sctdcenm Miclrc. \ar. strdiniiu'iiiii (Nash) D. Banks .A livmisid jihfolia Torr. Sporoholus aspcr ( Michx. ) Kunth Erogro.s/Z.s- tiicliodcs (Nutt.) Wood Boiitcloiid liirsuta Lag. Boittchnui aiiiipc'iulula (Michx.) Torr. Prosopis gidiululosd Torr. \iu". "laiuhilosd (Torr.) C-tx-kll. 5 Lime priekK ash Zdiillioxi/liiin faodra (L.) Sarg. Texas colubrina Colnbrind tcxciisi.s (T. 6c C.) Gray Texas persimmoTi Diospyms texaiui Scheele White tridens Tridtiis dlhe.sccns (N'asev) \Vo"urK mescjuite llilarid l)clans depending upon the range of plant heights (Table 2). An open-ended cul)e (250 mm on a side) was used to sample shrub and tree leaf biomass. The The ii.se ot a trade or linn name in this papi-r is tor reader inlornialion .ind does not in)pl\ endorsement In the U.S. Department of .-Vgrienhnre ol .in\ prixlnet or service. sample cube was placed in an area considered representatixe of the entire canop\', and the lea\es within the area were remoxed In* hand. LARs were determined in the same manner as for grasses. Within-plant \ariabilit\' of LARs was e\alu- ated for four mes({iiite trees and foiu" lime prickh' ash shnibs in Mav 1985 near Alice, Texas. Fifteen sample cubes were randomlv located and sampkxl from each of the four raes- (jiiite trees. For the lime prickK ash shrubs 12 sample cubes were hanested from each of the four shrubs. LAR was determined in the same inanntM- as pre\ionsl\ described. A one-wax' anal\ sis of \ariance was used to test for differ- ences (F < .05) among the slopes of the regres- sion e(juations within plant canop\' b\ species (Ste(>l and Torrie 1980). Within-plant LARs were not significanth' different for lime prickly ash and mescjuite hi May 1985. Based on these relationships, one sample per plant was utilized during the reinaind(M- of th(> stiuK. Three shrubs, lime prickK ash, Texas per- simmon, and Texas colubrina, and one tree. 19921 Raxcklam) Li-:af Area Kviios 241 Table 4. Mean and standard error of" leaf biomass and leaf area, and linear regression'' model slope coefficients (LAU lating leaf iUX'a to leaf bionuiss for selected rangeland shrubs and trei' on a line sandv loam range site near /Vlice. Texius. Species Date Leaf liiomass SE Leaf area (mm") SE LAR (nnn"g' ) r' Unie priekK ash Max- 19S5 4.7 0.73 45,180 1,450 8,760 a'' .99 Ang. 19S5 4.2 0.63 40,330 1,530 8,730 a .98 N(n-. 1985 5.6 0.89 43,360 1,460 8,670 a .98 Jan. 19S5 4.9 0.76 44,310 1,450 8,870 a .98 Apr. 19S6 5.3 0.65 52,730 1,580 8,690 a .98 \h'Sg\. and ecologx max find this species to be an excellent model lor colonization. Kci/ uonl.s: uwdusdhfdd. Tat'niatherum ca]")ut-mednsa(^ aiiiiiKil tr^rass. coloiiiziit^siwrii's. uihlfircs. grr/z///g. Ill the nianagemeiit of natural resources tlieii' are certain problems that 1)\ their persis- tence, inagnitnde of ecological disniption. and eeononiic impact refuse to dissipate as a result ol being ignored and neglected. UnFortunateK tor range management, niedusahead iTaoiidtlicrunt c(ipnt-})icdus(ic [L.] Nevski) is that t\pe ot problem. During the 1950s niedusahead was considered among the most pressing problems on the rangelands of C^alifor- nia, Idaho, and Oregon. A great deal of research effort was dexoted to solving the niedusahead problem, \aliiable information was learned about the ecoplnsiologs and s\niecolog\" of iiiechisahead. (Control methods were dexeloped using herbicides. The fatal link in integrated ])rograms for the suppression of niedusahead populations pro\ed to be artificial rexegetation technologies after niechisahead was controlled. The nature of tlu^ sites infested had more to do with this lailiire tliaii the weed itself, especialK in the bitermountain area. The recent discox'en ol niedusahead in northern Utah has renewcxl interest in suppressing tilis rangeland weed. M\ purpose in this review is to relresh our c()llecti\-e memories about medusaliead ecologx and management. Ta.xoxomv As is olten the case with an introduced s])e- cies, there has bec^i coulusion about the c'orrect scientific taxon lor medusaliead. Tlie first description ol niedusahead in a Nortli American flora used the tiixon Eh/iims caput-nwdiisac L. (Howell 1903). There is apparent agreement that niedusahead is a member of the trilx^ Triticeae of the grass tamil\-. There is also appar- ent agreement among moiphologists and c\ to- geneticists that niedusahead does not fit in the genus Elipmis. N'arious autliors haxc placed niedusahead in Hordciiin or Hordcli/iitits. Newski (1934) proposed tliat medusaliead was tniK" a different genus and published the name Tdcnidfhcrum. jack Major ol the I iii\ cisilx ol (California suggestcHl in 19f-)()tliat material intro- duced to the United States was Taeiiiathcnini (ispcriiiii (Major et al. 1960). Based on the European and Hussian literature. Major reported tliat I'dcuidlUcnitn contained three geograpliic and moiphologicalK tlistinct ta\a, T. cdjntt-incdnsdc. T. dsfxTiiiii. and T. crinituiii. Tlie.se three sjx'cies are loiiiid in the Mediterra- nean region and extend eastward into central .\sia. Alter examiiiiiiij; the European material, growing in place. .Xhijor decided the I iiited States introduction was T. d.spcruin. The Danish scientist Signe Frederikseii rexi.sed the genus in 19Sfl He kept the same three taxa, but reduceil them to subspecies of Tdciiiddici'iini cdpul-nicdusdc. Positixe identifi- .\griciiltmal Hesearcli Senice. U.S. Dep.irttm-iit c>IAi;ntiiltun-. 920 \all<-\ Hoad. Hi-iio. \\-\a(la Sy.5I2. 245 246 c;riv\t Basix Naturalist [Volume 52 cation to the lowest le\el possible is ahsolntely essential for am proposcxl biological control program for medusaheacl. According to Frederiksen's revision, subspecies crinituiii has a \'er\' strict spike. Subspecies captif-nicdiisae lias a large open spike with straight awais. The spike of subspecies a.spcniDi is intermediate with angled awns. Subspecies (ispcnim is die only one of the three witli pronounced barbs coated with silica on the awns. Apparently, the correct taxon for the medusahead of western North America is Tacniatlicnuu capiit-nicdiisac ssp. aspeniin (Simk.) Melderis (Frederiksen 1986). Taeniathenun caput-niedusae ssp. capiit- nicdiisae is mostK restricted to Portugal, Spain, southern France, Morocco, and Algeria. It has been collected outside this area in Europe and Asia, but Frederiksen considers it adxentitions in the.se areas. Subspecies chnitnt)i is found from (ireece and Yugosla\ia eastward into Asia. Subspecies aspcniiii completely overlaps the distribution of the other two subspecies. All three subspecies integrate with each other. ApparentK' onlv the one subspecies occurs in Nortli America. Does this indicate one or vev\ limited introductions? .Mechi.saliead is predominanth' self-polli- nated. Genetically the genus appears to stand alone in genomic relations within the Triticeae (Schooler 1966, Sakamoto 1973). ApparentK Tacniafhcrinii has a genome that is distinct, but faintK' related to those of Fsadii/rostachi/s, Dasijpi/nitii, Erciiiopiptim, or Hordcmii (Frederiksen and Hot hue 'r 1989). IIlSTOm- IN NOHTII Amkhica .Medusahead was first collected in the United States near Roseburg, Oregon, on 24 June 1 887 by Thomas Jefferson Howell ( 1903). It was next collected ncnu- Steptoe Butte in east- ern Washington in 1901 b\- George Xixsex (Piper and Beattie 1914), followed by a collection n(>ar Los Gatos, California, in 1 908 In Charles I litch- cock (Jepson 1923). Medusahead certaiuK attracted the noted agrologi.st. McKell. Hobin- .son, and Major (1962) commented on diis .strange initial distribution reaching 390 miles north and 450 miles south from the point of initial collection. EaH\ lied)arium .specimens show a rapid spread to the .south into California. J. F. PechantH- made die first collection in Idaho in 1944 near Payette or about ISO miles .south ol Steptoe Butte (Sharp and Tisdale 1952). Fred Rennertold jack Major he had seen medusahead near Mountain Home, Idaho, as early as 1930, and Lee Sliaq) had reports from ranchers that the species occurred in Idaho as early as 1942. The medusahead infestation in Idaho increased to 30,000 acres b\' 1952. Min Hironaka estimated that 150,000 acres were infested by 1955, and the Bureau of Land Man- agement estimated 700,000 acres were infested by 1959. At that rate of spread it appeared that all of Idaho would be infested by the end of the next decade. The spread of medusahead slowed and nearly continuous infestations remained confined to Gem, Payette, and Washington counties in southwestern Idaho. There were several spot infestations in surrounding counties (Hironaka and Tisdale 1958). Medusahead spread soutli in California to Santa Barbara on the southern coast and Fresno Count\' in the interior vallexs. The rapid spread from southwestern Oregon through northern and central California occiuTed in annual-dom- inated grassland, oak {Qtierciis) woodland, and chaparral commimities. These areas lia\e a Mediterranean t\pe climate with hot, di")' sum- mers and cool, moist falls, winters, and springs. Germination occurs in the fall and flowering and seed set in the spring. In northea.steni California, east of the Sierra Ne\ ada-Cascade rim, medusahead inxasion occiuTed at a much slower rate. In the Pitt Ri\'er drainage, vegetation is an intergrade of Oregon white oak (Qucrciis ^(irnjaiui) woodlands, cismontane California species, western juniper ifiiiupcnis occidental is), ponderosa pine {Pi)uis pondcrosa) woodlands, and sagebrush {Aifeini- .s7V/)/buncli grass communities more tspical of the Intennountain area. Medusahead was discoxt'red in the Great Basin at \erdi, Nevada, in the earK 1960s. Iso- lated inf(\stations were subsequentK found along the eastern front of the Sierra Ne\ada in ar(>as wliere range sheep bauds used to concen- trate^ wliile waiting for mountain summer pas- tures to be Iree of snow. In northeastern C'alifoinia in the CTreat Basin duiing (h(" earl\' 1960s, tluM'e were two small inlestations in citv lots in Snsanxille and a small infestation at the old slu^ep-shearing site of \iew land along the niilroad above Wendel, Cal- ilornia. .Another isolated infestation occurred at die mouth of Fandango Pass in Suiprise Valley. B\ the earK 1970s, medusahead was uearK" 19921 ECOlXKiY AND MANA(;KMENT()F MKDI SAIlKAl) 247 continuous ox'er al)out 60. ()()() at'ics of tlic Willow (]reek-Tal)l('Ian(ls northeast ol Susan- \illc. ('uncntK. alter lour \ears ol extreme (lrouu;iit. uiedusahead s[)()t iutestatious occur o\tM- [)erliap.s an additional uiillion acres on the westcM'u maitjiu ol the (weat Basin. HlOl.OCV OF MEI^USAIIIvM; Medusaliead. in some wavs, is a rerun of clieatgrass {Bronms tectoniin) imasion. (dieatgrass dominates secondan' succession in a majorit)' of sagehnisli/bunchgrass communi- ties in the Great Basin and proxides a significant portion of the forage base for lixestock grazing. Howe\er, there are hiiihK' si(j[nificant differ- ences in the ecolog\- of the t^vo grass species (Harris and Wilson 1970, Al-Dakheel 1986). Germination. — The canopsis of medusa- head is less than a millimeter wide with a \en shaip callus and an elongated, non-geniculated awii. The medusaliead caiyopsis is covered with small barbs of silica. \^cious is the best descrip- tion for this grass canopsis. Bo\e\" et al. (1961) determined that medusaliead had a much higher ash content (o\er 10%) than other grass species and the ash was about 7o7c silica. Hea\A' deposition of .silica occurs on the barbs of awns and the epidermis of leaxes. For the \ast majorit\ of collections of cheatgrass from the Intermountain area, seeds are ready to germinate when tlun are mature. No pregermination treatments are necessar\ (Young and Exans 1982). For collections from the Great Plains and perhaps the Columbia Basin, seeds may have a brief afterripening dor- mancy. In contrast, seeds of medusaliead have a temperature-related afterripening, and germi- nation will not occur except at cold incubation temperatures for about 90-120 daws after matn- ritx (Young et al. 1968). Nelson and Wilson ( 1969) found this (loi-manc\ was eontiolled In niat(M-ials located in the awn. The high silica content on the herbage of medusahead makes the litter xen slow to decompose. Harris (1965) described Hie chok- ing accumulations of medusahead litter that built up for sexeral \ears. We exalnated the germination of seeds of \arious annual grass species in medusaliead litter (Young et al. 1971a). Allelopathy was not suspected, but rather the ph\ sical holding of seeds out of contact with the surface of the seedbed. Medusahead seeds ger- minate \-er\- well without the callus end of the seeds touching a moisture-supplving substrate, bi this situation, germination of medusahead seeds is controlled In' the relatixe humiditx within the litter and tlie incubation tempera- ture, which of course influences the relatixe humidity. The needlelik(\ xitreous carxopses of medusahead appear hxdrophobic rather than hygroscopic. Not ouK' can medusahead seeds germinate under diese conditions, but thex can be dried until the priman- root is dead; then, lolloxxing remoistening. a nex\- adxcntitious root xvill dexelop. Raxuiond Exans and I demonstrated x\ hat a great modifxing influence litter coxer can be to the surface of seedbeds on temperate desert rano;elands in terms of n^dncing extremes in temperature and consening moistm-e (Exans and Young 1970, 1972). (^anopses of s(juirreltail {Eh/nuis In/strix) are xcn- similar in moqihological appearance to those of medusahead. As I xxill discuss later, s(juirreltail seedlings are one of the fexx- natixc species that can become established in undisturbed medusahead stands. Both Tacniaflicniin and Ely nuts are members of the tribe Triticeae, but thex" do not share the same genome. Medusahead populations easiK- exceed 1000 plants per square foot, and thex- are phenotxpi- callx' plastic enough that a population of 1 plant per square foot can exceed the seed production of 1000 plants per square foot (unpublished research, ARS, Reno, Nexada). Huge seed banks dexelop in medusahead conunuuities in the litter and .soil. Medusahead seetl accjuires a dormancx in the field similar to that of cheatgrass (see Young et al. 1969). The.se dor- mant seeds respond to eiuichment of the seed- bed xxith nitrate and gibberellin (Exans and ^bnug 1975). Life cycle. — Medusahead seeds can ger- minate in the fall, xxinter, or spring; and seed- lings liom all seasons can j^roduce fioxx'ers and seeds earix in the sunnner. The striking thing about the medusahead life cxcle is that it matures from 2 to 4 xveeks later than other annual grasses. All those famous botanists and range scientists xx'ho xxere out on the range di.s- coxering nexx- infestations of medusahead xx'ere led to the populations In the bright green color xx'lien all other aimuals in either cisniontane Galifoniia or the Great Basin xvere broxxn. R. L. Piemeisel recognized the dominance of alien plant species in the secondan succes- sion of disturbed satiebrush communities in the 248 (;rk,\t Basin Naturalist [\ oluiiie 52 InterniounUiin area (PicMiieisel 1951). Wbrkiiiii; on the Snake Rixer plains of Idaho (hirinS9-.397. Fkedebikskx. S.. anci R. \'()N BcrniNKK 19S9. Inter- generic Inhridization between Tacniathcnun and dif- ferent generae olTriticeana Poaceae. Nordic [ourual of Botan\- 15: 229-240. GOEBEL. C. ]., and G. Bi luiv 1976. Selectivih- of range grass .seeds bv local birds. |oimial of Range Manage- ment 29: 39.3^395. H.-\BHIS. G. .-v. 1965. Medusaliead competition. Pages 66-69 in Proceedings of the Cheatgrass Svnnposium, Vale. Oregon. Bureau of Land Management, Portland, Oregon. PUhiuS. G. a., and A. M. Wll.sox. 1970. Competition for moisture among seedlings of annual and perennial grasses as influenced bv root elongation at low temper- atures. EcologN 51: 530-534. Hll.KEN. T. O., and R. F. Mili.EH I9S0. Medusaliead {Tdcukithcnnii a.spcniui Ne\'ski): a re\iew and anno- tated bibliographv Station Bulletin 664. Agricultural Experiment Station, Oregon State Uni\'(^rsit\', Conallis. HiBONAK.A. M. 1961. The relative rate of root development of cheatgrass and medusaliead. founia! of Range Man- agement 14: 26.3-267, HiKONAKA. M.. and B. W. Sindki.ah 1973. Reproduction success of s(|nirreltail in medusaliead infested ranges. Journal of Range Management 26: 219-221. . 1975. Growth characteristics of scjuirreltail seed- lings vs. competition with niedusahead. |onrnal of Range Management 28: 283-2S5. HiHONAKA. M.. and E. W. Tisdai.e. 1958. Relati\e roK' of root de\elopment of medusaliead and cheatgrass. Page 28 hi Progress Report. Western Weed Control C-onfer- ence. . 196.3. Secondarx succession in annual vegetation in .southern Idaiio. Ecologx- 44: 810-812. HoKTON. W. II. 1991. Medusaliead: importance, distribu- tion, and control. Pages 387-394 in L. F. |ames, |. O. Evans, M. II. Ralphs, and R. D. Childs, eds.. Noxious range weeds. Westvitnv Press, Boulder. Colorado. lloWEl.l,, T. 190.3. A flora of northwest America. \ol. 1. Phanorogamae. Binford and Mort, Portland, Oregon. JeI'son W. L. 1923. .Annals offlowering plants of California. SatlierGate Bcx)k.shop, Berkelew CiJiforuia. ICw B. L. 1963. Effi^cts of dalapou on a medusaliead coui- iiinnit). Weeds3: 207-209. ■ 1966. Para(jnat for set-ding without cultixatioii. Calilomia .-Vgricultnie 20: 2-4. K.\V. B. I,., and C. .M. McKKl.l.. 1963. Pre-emergcuce her- bicides ;ls an ;iid on sc-edling annual raugeland. Weeds 11: 260-264. LUSK. W. C. M. B. Jones. D. T Tokei.i. and C. M. .VIcKell. 1961. Medusahead palatabilitx. |ournal of Range Management 14: 248-251. ,\1,\|()H |.,C:. M. McKfi.i. and L.J. Behky 1960. Impnne- ment of medusaliead infested rangeland. California Agricultural Experiment Station Extension Senice Leaflet 123. .Mali.oky J. 1960. Soil relations with niedusahead. Pages 39—41 in Proceedings of the California Section of the Society for Range Management. Fresno, California. McKell. C. M., J. P. RoBisfix and J. Major 1962. Eco- txpic \ariation in niedusahead, an intnuluced annual grass. EcologN' 43: 686-698. M( Kele, C. M., .\. M. WUson, and B. L. K.\v 1962. Effec- ti\e [)uniing of rangeland infested with medusahead. Weeds 10: 12.5-131. Nelson. J. R., and A. M. Wilson, 1969. Influence of age ;md awn removal on dormancy of medusahead seeds. |()urnal of Range Management 22: 289-290. xNi:\SKL S. A. 1934. Schedae ad Herbarium Florae Asiae Mediae. Acta LImu Asiae Med \4IIb. Botanica 17: 1-94. PiE.MElsEL R. L. 1951. Causes affecting change and role of change in axegetation of aimuals in Idaho. Ecolog\'32: 5:5-72. Pll'EK C. \'., and R. K. Be.VPTIE 1914. Flora of southwest- ern Washiiigtou and adjacent Idaho, The New Era Printing Co., Lancaster, Penn.sxKania. S\K\MOTO. S. 1973. Patterns of plivlogenetic differentia- tion in the tiibeTriticeae. Seik Zilio 24: 1 1-.31. S\\ \(:e D. E., J. A. YoUNC:. and R. A. Evans 1969. Utili- zation of medusahead and down\ brome ciuAopses by Chnkar Partridges. Journal of Wildlife Management .33:97.5-978. ,Sgiiooli;h A. B. 1966. Eh/niu.s caput-nicchi.snc L. crosses with Af'^ildjis ci/liiulricii host. Ch"()p Science 6: 79-82. Smahl, L. .a. and E. W, Tisoale, 1952. Medusahead, a problem on some Idaho ranges. Research Note 3. Poorest, \Mldlife and Range Experiment Station, Uni- \ersitx of Idaho, Moscow. YoLNG, |, ,\,, and R. A. E\ \Ns 1970. Inxasion of medusahead into the Cweat Basin. Weed Science 18: 89-97. . 1982. Temperature profiles for germination of cool season range grasses. .'\RR-W-27. .'\gricultuial Research Service, USDA, Oakkuid, C';ilifornia. Yoi Nc j. A.. R. A. Evans, and R. E. Eckeht. Jk 1968. (Ti'rmiuation of mechisahead in response to tempera- ture and aftenipening. Weed Science 16: 92-95. . 1969. Population cKnamics of downx' brome. Weed Science 17: 20-26. YcUNG. J. A., R. A. ExANS, and B. L. Ivxv 1971a. (iermina- tion of carxopses of annual grasses in simulated litter Agrononix' [ounial 63: 551-555. . 1971b. Response of niedusahead to paiaijuat, |our- iial of Range .Management 24: 41—43. Y(U NO |. A.. R. A. Ex'ANS. ;uid J. M.^JOK 1977. Sagebrush ste])pe. Pages 76,3-797 in M. G. Barbour and |. Major, eds.. Terrestrial xcgetation ol ( !aliloi iiia, John Wllex & Sons. New York. YoLNc; |. A. H. \, F,\ \\s and j. Hi HsisdN 1972, Influence ol repealed animal buruiiig on a nu'dusalieatl conimn- iiitx, |ouniai ol Range Management 24: 451-4.54. Rrccivnl 2:Ulai/ Um Arrrpird 22 Jinir I9h)2 (ireat Basin Naturalist .")2i.'Vi. pp. 25o-2Hl R(X)ST SITES USED BY SANDHILL CRANE STA(;iNG ALONG THE PLATTE HI\ EK. NEBRASKA Bra(lle\' S. NOrliiiii; , Staiilcx 11. .VikIitsoii , and Wiune A. Iliihcrf .•\bstiu(X — We iLssessed the influence of water depth, extent of unobstructed \ie\\\ and huiuan disturbance features on use of roost sites h\ Sandliill Crimes along the Platte Ri\er, Nebraska, during .spring niigraton stopox er. .Xt'riai photos tiikcn near dawn were used to determine areas of flock use and habitat a\ailabilitv in four sample reaches, and measurements were made on the ground at flock roost areas. In general, depths of 1-13 cm were used bv s;uidhill cranes in greater proportion than those a\ailable. Exposed sandbars ;uid depths >20 cm were a\()id(^d, wliile depths of 14-19 cm were u.sed in proportion to their a\ailal)ilit\-. Sites 11-50 m from the nearest \isual t)bstruction were used significantly greater than their availabilit); while sites ()-4 and >50 m from \isual obstnictions were avoided. Sandliill Cranes avoided sites near pa\ etl roads, gra\el roads, single dwellings, and bridges wjien .selecting roost sites: howewr. thex' did not appear to be disturiied b\ private roads, groups of residential buildings, graxel pits, railroads, or electrical trausniissioii lines. Kc'i/ words: Sdiulliil! Crane. Cirus canadi-nsis, river rocistn. habitat .sclcclioii. water di])th. (li.slurhanrc. saiulhars. Platte Hirer Tlie impact of water re.sourcc^ clex'elopnieiit on the Platte Rixer i.s well described (Kroonemever 197S, Williams 1978, Eschneret al. 19S]. Kii-cherand Kariinger 198L U.S. Fish andWildlite Senice 1981. Krapn 1987, Sidle et al. 1989). The major impact lias come from irrigation projects along the North Platte Ri\er (Krapn et al. 1982), which remo\e approxi- mately 70% of the annual How of the Platte Ri\er before reaching sonth central Nebraska (Krooneme\er 1978). Concomitant with chan- nel shrinkage, woocK' vegetation has encroached on thonsands of hectares of former channel area, contributing to further changes in channel features and altering habitat for numerous .spe- cies of migraton- birds in tlie Big f^end Reach of the Platte River in Nebraska (U.S. ImsIi and Wildlife Sei-vice 1981). The Big Bend l^eacli of the Platte Ri\er in Nebraska is an area of importance to numerous sjiecies of migraton birds ol the Central I^1\\\a\ ( If.S. Fish and Wild- life Senice 1981 ). This area is an important stojioxcr area lor most of the midcontin(mt population of Sandhill Cranes (Cms i-ditddciisis^ i 4(H ).()()( )--6( )().()()() birds), which roost in the riwr and feed in neadn com fields (Krapn et al. 1981, Krapn 1987). The endangered Wliooping Cj-ane (C^, (iincricdiui) also uses the area during migration, and the tlu'eatened Bald Eagle {Haliacctus lei(coccpJialiis) is a common winter resident (U.S. Fish and Wildlife Senice 1981). The area is also important habitat for the endangered interior population of Least Tern {Sfcnia aiitil- lantm) and the threatened Piping Ploxer (Charadriiis niehxhis), both of which nest along the Platte Ri\er (U.S. Fisli and Wildlife Senice 1981, Sidle etal. 1989). Considerable attention lias been gi\en to the impact of changing channel conditions on the midcontinent population of Sandhill Cranes {Gnis canadensis) that congregate along the riverfront earl\' March to mid-,\pril during their animal spring migration (Lewis 1977, Krapn 1978, U.S. Fish and Wildlife Senice 1981). During this time approximatcK 4()(). ()()() Sand- hill Cranes use tins an^a while euroiile to their breeding grounds in (Canada, Alaska, and eastern Siberia (U.S. F^ish imd Wildlife Senice 1981). In Nebraska various facets of Sandhill Crane roosting habitat rectivel\. across the Cireat Plains to their confluence near North Platte, Nebraska. The stnd\' area is characterized b\ numerous braided channels interspersed with imxege- tated sandbars that fre(juentl\" shift. Most of the land within and adjacent to the stuch' area is in private ownership. Land use in the area is pre- dominantly agriculture and includes approxi- mately 60% cropland (mostly com), 5% tame pasture, 20% nati\e grassland, and 15% riparian woodland (Keinecke and Krapn 1979). The riparian woodland comprises eastern Cottonwood (Poptthis deJioidcs) forests with (k)minant understoiA species of red cedar (Jiinij)rrii.s lir^inidiia) and rough-leaf dogwood (doniu-s (Innnmotidii). On low islands and \eg- etat(^(l sandbars, peach-leaf willow {Salix aini/i^ddloidcs). ccnote willow {S: cxig^nal), and indigo bush (Aniorplia fnitirosa) are the domi- nant species (U.S. Fish and Wildlife Senice 1981, Currier 1982). MKTHODS .Aerial photographx was used to determine flock locations and delineate flock boundaries of 19921 CiiWE Roost Sites roosting Saiulliill Cranes along a 36-kni stretcli ot the Platte Hi\{M-. Photograpln" was restricted to mornings with less than 10% cloud coxer and ceilings abo\e 975 m. Flights were begun 30 minutes ht^fore sunrise ])ecanse ol the need to pli()t()gra[)h Sandhill C'ranes before the\' lea\e the roost in earl\' morning. Light was adequate to piMinit photograph\' 10-15 minutes before sunrise. A Hasselblad 500 P.L, 70-mm camera was used to photograph the stud\' area. The camera was mounted in a standard camera hatch in a Cessna 172 fixed-wing aircraft and was equipped with an SO-mm focal length Zeiss lens. Exposures were made at 1/60 and 1/125 second at f2.8 using Kodak Tri-X 640 AFS Aerographic film. The camera was equipped with a 70 expo- sure back loaded with 5.5 m of film allowing 2() m. Flocks usnallx' occurred in configurations that a[)pear{>d distinct from other flocks in the xic initx. After transects xx'cre located on [)hotograplis, thex" xxere measured and laid out on the ground in relation to marker locations using \inx 1 flag- ging placed on each side of the channel. Water depths xxere measured to the nearest 3 cm at 3-m inten als and plotted on acetate oxerlaid on aerial photogra]:)hsx\ith delineated flock bound- aries. Width and depth data xx^ere combined to gix e mean estimates for each of the four reaches. Each 1.6-km reach xvas sampled as soon as possible after each flight, alxvavs xvithin three dax's. Staff gauges xxere placed in each area to measure anx* changes in xxater lexel between the time each reach xx'as photographed and the time it xvas sampled. Detectable changes in xxater lex'el xx^ere recorded and used to con-ect dt^pth distributions. Discharge xvas measured on each flight dax' in close proximity' to the study areas folloxxiug the techni(jue of Buchanan and Somers (1969). Contact prints xxere made from each roll of film. Indixidual frames xx'ere cut out and glued onto posterboard to form a mosaic, proxiding a continuous coxerage of the rixer channel. Scale was determined bx' comparing bridge segments and transect locations on the contact prints xxith measurements of these locations niadc^ on the ground. Scale e,stimates were made along 2- to 3-km segments of rixer Photograph scales ranged froiu 1 :8,681 to 1:1 0,334 for the first txxo flights, and 1 : 10,595 to 1:11, 857 for the last txx'o flights. A binocular zoom iuicro,scope (1-4X) xx^as used to ick^ntifs flocks and delineate flock boundaries on the contact prints covered xxith ac(Tatc. Flocks wcic delineated and subse- (juentK nmubered on the acetate oxerlax'S on contact photos. The distance from the edge of each flock to the nearest xisnal obstniction x\as measured to the nearest 0.5 nun on the photos (ground distance = ^6 m) using a drafting cal- iper \ isual obstructions inclnck'd xegetation, a rixer bank, or anx otlier 'xisualK solid" object >1 m in height. Kandom points were plotted on contact photos to (\stimate the featm-es of ax ailable hab- itat. Ranck)m points xxere determined bx a .series 256 G H EAT B AS I N N ATU R A LI ST [\ bluiiie 52 of random numbers identifying point coordi- nates on gridded overlay coxering contact prints. Points outside the rixer channel were discarded. Onl\- random [X)ints located in water were u.sed because points on sandbars, islands, or the ri\er bank were not considered poten- tiall\- usable roosting habitat. A total of 339 random points within the ri\er channel were identified on the contact prints. Grid squares were 1.25 mm" to ensure a representative sample of locations on the ri\ er. As with flock locations, the distance from each random point to the nearest \isual f)bstruction was measured on the photos t(; the nearest 0.5 nun using a drafting calipei-. For analvsis oi human disturbance features, flock locations and random points along the entire 36-km stud\' area were transferi-ed from 70 nun contact prints to acetate overlays of color infrared aerial photographs (scale 1:25,595) using a zoom transfer scope. The photographs taken in April 1989 were obtained from the Bureau of Reclamation in Cirand Island, Nebraska. Distances were measured from the edge of each flock and individual random points selected b\' placing a card over the photograph to the nearest human disturbance features. These features included pa\ed roads, gravel roads, prixate roads, urban dwellings, single dwellings, railroads, connnercial development, highwa\s, and bridges. Distances were mea- sured to the nearest 0.5 mm on photos (ground distance = 13 m) with a drafting caliper. Data AnaK sis FrequencN' histograms were plotted for mea- sured distances from the edge of a flock and for random distances to the nearest visual obstruc- tion and disturbance features. Frequencv distri- butions were plottc>d for axailable and used selected water depths. Fre(jU(Mic\- distributions of available and used selected water depths for each 1 .6-km reach were determined bv combi u- ing flock data for each reach for a given flight. Available depths were defined as all depth mea- surements taken along a transect, and used depths were those depths where birds were present along a tran.sect. Habitat selection v\as computed by dividing the proportion of habitat u.sed within a depth intenal bv the proportion of depths available in that same intenal (Bovee 1986). Depths used less than their availabilitv' were defined as being av oided, while those used more than their availabilitv were defined as being selected. Habitat avail abilitv, use, and selection were summarized within reaches, across flight dates, and from data pooled across reaches and flight dates. Data were pooled to generalize the selection of depths over the course of the sampling period. The chi-sqiuire of homogeneity (Marcum and Loftsgaarden 1980) was used to test whether differences existed between the distri- l)utit)n of random points and those locations used bv Sandhill Cranes relative to visual obstructions and distiu'bauce features. It was also used to determine if there were differences between the proportion of used and available water depths among and within reaches. Confi- dence intervals were calculated using the Bonferroni Z-statistic to test which intenals within the distributions were used more or less than exjDected (Byers et al. 1984). Differences between selection functions were tested wdth a Z-test. Analysis of variance (ANOVA) was used to determine if visual obstructions had an effect on the disturbance potential created by various tvpes of disturbance features. Significance for all statistical inferences v\'as P < .05. Results A total of four sampling flights were made: one each on 21 and 31 NIarch and 4 and 10 April 1989. A total of 285 flocks were identified during the four flights. Folkming the flights, 20 flock sites vwre selected and sampled and a total of 5109 depth measurements were recorded in the field. Sampling areas. — Reaches I and II were the narrowest, with mean channel widths of 254 m (range = 225-319 m) and 249 m (range = 241-263 m), respectivelv, while reaches III and I\', located upstream, were wider. Reach III had a mean channel width of 413 m (range = 387- 440 m), while reach W had a mean channel v\idth of 357 m (range = 296-445 m). Reaches I and II had similar discharge (17 mVs), while reaches III and l\ had greater values (27 and 44 m Vs) on 21 March (Table 1 ). Discliarge in rcnich III was tvpicalK tv\ice as high as reaches I and II. Reach 1\' had the highest discharge of the four reaches, often three times greater than in reaches I and II (Table 1). Reaches I, II, and III were located in a braided portion of the surface along the south chaimel and coutaineil onlv partial river flow. 19921 CiuxE Kous'i' Sites 25' TaBI.F, 1. Disc-lianji;e in cubic meters per second (m ) for saiii|ile reaclu's on tlifTerent i'\\'j}]\ dates alon<4 tlie Flatte Ui\er Nebraska, during spring 19S9. Flight date Reacli I Reach II Reach III Reacli I\' 21 March-' 31 March 4 April 10 April 17.4 11.1 10.6 7.9 17.4 10.6 7.9 27.5 18.6 13.7 44.6 32.1 2S..S 21.7 ■'Discliarge.s for all reaches on 21 March were nieasiircd cm 24 Maich. TIids. a lhii'i'-ila\ la;; |)rrio20 cm) occurred o\er the stud\ period. This di\ision is made because cranes seldom used depths greater than 20 cm. The increase in exposed sandbars (depth = 0 cm ) was most pronounced in reaches I and II, which showed increases of 13% and 11%, respecti\el\ . Reaches II and III showed increases of 12% and 19%, respectiveK', in axailable depths of 1-4 cm betAveen the first and last flight. Reaches III and W showed decreases of 10% and 7%, respec- tixcK; in depths >38 cm for the same period. During the stiuK period a progressixe decrease in discharge occurred (Table 1), causing more shallow areas (0-19 cm). HabiT.AT use. — Frequency di.stributions of roosting habitat use hv cranes indicated the liighest proportions of used water deptlis were from the 1-4 and 5-7 cm increments. This range ot water depth accounted for 65% of the mea- sured depths. There was no discernible \'aria- tion in the frequency of water dejiths us(^d among the four reaches. There was a small, but significant, difference in tli(^ distribution of depths used bet^\•een the beginning and end of the study period (F < .05). Depths of 0 cm showed a significant decrease in use, while depths 20-22 cm sliowed a signihcant increase in use {P < .05). The data showed a significant difference between the distribution of used and available water depths for all foui- sampling periods (P < .001). Sandhill Cranes used progressiyely deeper water depths as the stud\ season progressed. Depths >20 cm were used significanth- less than expected during the first flight; but, b\- the last sune)', only depths >29 cm were used less than expected {P < .05). Depths of 0 cm were generally avoided bx Sandhill (>ranes during the last two sur\e\ s and were used less than woidd be expected bx chance (P < .05). Habitat selection was assessed using both habitat use and axailabiHtv' data for specific water depths. The most frecjuentK occurring depth intenals for which selection occurred were 5-7 cm, fcjllowed by 1-4, 8-10, 1 1-13, and 14-16 cm in decreasing order of preferenc-(\ Visual (obstructions. — There was a sig- nificant difference between the distribution of flock locations and random points reiatixe to the distance from the nearest \isual obstruction (F < .001). Proportional u.se of sites 0-50 m from the nearest \isual obstruction was signifi- canth' greater than a\ailabilit\ (F < .05), while sites >50 m from a \isual obstruction were avoided (F< .05). The 0-25 m interval was di\ided into six increments: 0, 1— f. 5-10, 11-15. 16-20. and 21-25 m. There v\as a significant difference lK^t^\'e(^u the distribution of flocks and random point distances (F < .001 ). Sites as close as 5-10 m from the nearest visual obstruction were us(^d by Sandhill Cranes. Onlv sites 0 — f ni from a \ isual obstruction v\ere avoided (F < .05), while sites 1 1-25 m from a visual obstruction were used more than expected (F < .05). Msual obstructions v\ere divided into three categories: (1 ) unvegetated bank. (2) \egetated bank, and (3) xegetaled island. There v\'ere no significant differences in the distribution of dis- tances b(^h\een an unvegetated and vegetated bank, but there were significant differences for tlie distribution of distances between vegetated banks and vegetated islands and between unvegetated banks and vegetated islands (F < .005). Sandhill Cranes roosted a mean distance 258 Cheat Basin Naturalist [\'()]unie 52 of 45 Ml from umegetated banks. 50 in lioni wgetated hanks, and 27 ni from v{>o;etat('d ishmds. Channel width. — ^There was a ndation- ship between the niinimnm unob.stnicted chan- nel width and distance to the nearest \isiial obstrnction. The distance to the nearest \'isnal obstrnctions was ahuiction of less than one-half die niininnnn unobstrncted channel width. There was a significant difference between the distribntion of flock locations and random points relati\e to minimnm nnobstructed chan- nelwidth (P < .005). Sandhill Cranes used chan- nels 100-200 ni wide in greater proportion than tho.se generalK a\ailable. Channels narrower than 100 m were axoided, while those >200 m wide were used in proportion to their axailabil- ih'. The mean minimum unobstioicted channel wudth used by roosting flocks was 196 m (range = 34-445 m).' Nearly 100% of the flocks we re hi channels with a minimum unobstructed chan- nel width of >50 m, and over 97% and 80% of the flocks were in channels with a minimum unobstructed width of >]()() and >150 m. respectixeK'. The mean relative flock size (sui- face area) was 3883 m~ (range = 19-55,354 nr). There was no relationship between flock size and minimum nnobstructed channel width. Both large and small flocks were located in wide, as well as narrow, channels. liiiinaii Disturbance Features PWKi:) KdADS. — Sandhill Crane flocks were not distributed randoniK with respect to dis- tance from pa\ed roads (P < .001 ). Sandhill Cranes showed avoidance of sites closer than 500 m from the nearest paved road (P < .05), but used sites as clo.se as 301-400 m. Sites located 701-900 m from the nearest paved road were used mon^ than expected (/' < .05). Sandhill Cranes roosted a mean distance of 12fiO m from the nearest paxed road when a \isual obstrnction was present, but a uK^an dis- tance of 1575 m from the nearest paved load in the absence of \isual obstnictions. C;ra\'EL roads.— There was a significant difference behveen the distribution of used sites and random locations relative to tlistance from gra\el roads (F < .01). Sandhill Cranes showed a\()idance of sites that wert> closer than 400 m from tiie nearest graxel road (F < .05), but flocks were located as close as 301-400 m. Sites that were 601-800 m from the nearest gravel road were used more than expected (F < .05). The presence of \isual ob.struction between a roost- ing flock and the nearest gravel road did not appear to reduce the disturbance potential cre- ated bv gravel roads. Sinc;LE D\\ELLINC;S. — There was a signifi- cant difference between the distribution of used and random locations relative to the distance to the nearest single dwelling (F < .01). In general. Sandhill Cnuies showed an axoidance for sites closer than 400 m from a single dwelling (F < .05). Sites 501-600 m from the nearest single dwelling were used more than expected (F < .05). The presence of a visual ob.struction between a flock and the nearest single dwelling did not affect the disturbance potential created bv single dwellings. Bridces. — Sandhill Crane flocks were not distributed randoniK with respect to distance from bridges (F < .001). They showed avoid- ance of sites closer than 400 m from the nearest bridge (F < .05). Similarly, they used sites >400 m from the nearest bridge. Other disturbances. — No significant differences were found between urban dwell- ings, gravel pits, commercial development, transmission lines, and the distribution of Sandhill ('nine flocks. Discussion Depth Distribution. — Tliis study indicated that Sandhill Cranes prefer water depths of 1-13 cm for roosting but roost in greater depths. Lataka and Yahnke (1986) developed a predic- tive model for Sandhill Crane roosting habitat and stated that the majorih' roosted in water depths between 0 and 12 cm, which is presum- ably the optimal depth for roosting. Similarly, Frith ( 1986) suggested a water depth of 2-15 cm as optimum for roo.sting sites. Currier (1982) reported a slightlv deeper range of depths from 10-1 5 cm as optimum for roosting. Lewis (1974) suggested that loost sites be characterized bv deiiths 10-20 cm, and Folk (1989) reported an even greater range of depths used for roosting: 0.1-21.0 cm for Santlhill (Cranes along the North Platte Ri\ t-r in Nebraska. D(>spit(' a change in the availabilitv of water (k'pths with over a 50% reduction in discharge oxer the period of study (Table 1), onlx' slight differences xvere detected in the oxerall use of specific water depths. The fact that habitat use remained tlu^ same despite a change in habitat selection sut£tiests that selection indices more 19921 Cham-: Hoost Sites 259 str()n>j;K rclclcct cliaiiiics in liabitat a\ailal)ilit\ than habitat preference. If habitat sc^lcn'tioii had reflected hal)itat preference, then habitat selec- tion indices wonld ha\e been more similar between tlie beginning and end of the stnd\ period. X'l.Sl AL ()B.STRUCTIO\S. — This .stnd\- indi- cated that Sandhill Cranes will not roo.st closer than 5 m from a \isual obstniction and that distances from II to 25 m are the most fre- (jnc^ntK used, batkaand Yahnke (1986) reported that Sandhill (>ranes did not roost 25 m from a \isual obstruction, but he obsened roosting as close as 4 m from a \isual obstniction. Our results indi- cate that \arious forms of visual obstiiictions liaxe different impacts on roost site selection. 0\erall, \egetated islands ha\e little influence on the selection of roo.st sites, whereas \ege- tated banks ha\e greater influence. It is generall\- beliexed that Sandhill (Cranes maintain an optimum distance from a \isual obstruction to increase their securits' from ter- restrial predators, primariK' candids. This is e\i- denced by the fact that the majorits' of flocks are located in closer pro.\imit\' to \egetated islands than to unxegetated or \egetated banks. Channel moipholog\' ma\' also be a factor influencing the distribution of roosting areas relati\e to banks or islands. This assertion is supported bv obsenations from depth measure- ments which suggest that water (k^ptlis and \elocities near l)anks are deeper and faster than (k'pths near islands due to bank inidercutting. Thus, sites near islands mav contain a greater proportion of suitable roosting depths than sites adjacent to banks. ClIAXXEL WIDTH. — Sandliill Cranes .selec- tixely used channels 10()-2()() m wi{k\ while channels narrower than lOO in were axoided. Nearl\- ]{){)7r of the roosting Sandhill ( irane flocks were located in channels with an unob- structed channel width >5() m, and oxer 8()9f were located in channels >15() m wide. Wuk^ channels potentialK proxide mor(^ space for roosting Sandhill Cranes, more securits from predators, and more axailable water tlepths to choose from. However, since channel width w as evaluated independentK- of channel depth, it is possible that use of narrow channels (<1()() m wide) is limited not so much bv a requirement for wider channels, but b)- deeper water that flows through these chaimc^ls ( Latkaaiid Valinke I9Sfi). Oui" findings corroborate the results of Krapu et al. ( 1 9S4 ). w ho reported that o\er 997f of all roosting Sandhill (Cranes were in unob- structed channels o\er 50 m wide and almost 7()9f were in channels > 150 m wide. In contrast, data from nighttime aerial thermographx In- Pucherelli (19S8) suggested that almost half of all roosts were in cliannels <15() m wick' and that the greatest proportion of roosts were in channels 51-150 ni wide. Folk and Tacha (1990) studied roosting along the North Platte River in Nebraska and reported a channel width criterion that was dif- ferent from this study, Thev reported that 82% of the roosts were in channels >48 m wide and 18% were in channels from 16-47 m wide. HUxMAN DISTURBANCE. — Our stnd\ (lemon- .strated that human disturbance features influ- ence selection of roost sites b\- Sandhill Cranes. In general, the greatest disturbance potentials were attributed to roads (pa\ed and graxel), bridges, and single dwellings where irregular but considerable hiuiian acti\it\- might occur. Cra\el pits, private roads, railroads, and power lines had infrequent disturbances and did not seem to affect roost site selection. In iill likeli- hood some form of acclimatic^n occurs between the constant disturbance on comnuM-cial and ui'ban development. There is little literature that objectively describes the zones of influence exerted bv var- ious human disturbance features on the selec- tion of roost sites bv Sandhill ('ranes along the Platte River. Folk (1989) suggested that riparian forest along tlu^ river provides a visual barrier against most tv pes of potential disturbances and that Sandhill ( Cranes roost in sections of the river as close as SO m from a bridge. In contrast, our studv intlicales that Sandhill Cranes roost in sc^ctions of the river that are >400 m from the nearest bridge. We feel that our results provide an ol)jectivi' description of potential zones of influence e.xerted bv various disturbance fea- tures and tlu^ (4Tect tliese leatm-es have on roost site selection bv Sandhill Cranes along the Platte River. In sunnnan. our studv shows the importance of sandbars with water less than 20 cm in depth surrounded by deeper water. These sandbars must be at least 5 m from some form of visual obstruction such as dense vegetation. This apparentlv allows the Sandliill Cranes to see 260 Gi^KAT Basin Natui^alist [\'()luiiie 52 approaching predators. As a result. Saiulliill Cranes nonnalK' roost in channc^ls l()()-2()() ni wide. These sites are general I\ a\\'a\- from human disturbances such as roads, bridges, and prixate dweHings. Sandhill (>ran(\s could toler- ate irregular disturbances such as private roads and railroads. Tlie fact that 80% of the midcoutiueut pop- ulation of Sandliill CJranes uses this area for staging in the spring indicates its importance. It is during this period that the birds apparently build up energ\' resenes allowing them to con- tinue their northward migration. If the area were to become imlit for Sandhill Cranes, the population would likeK sulfer decline. ACKNOWLEDC; M E NTS We appreciate the help ol Delmar Holz, Laura Smith, and Craig Schwieger of the Grand Island, Nebraska. Office of the U.S. Bureau of Reclamation, who supplied needed equipment and assisted in the field. The U.S. Fish and Wildlife S(M-\1ce personnel in Grand Island, especialK" Jerrv' Brabander, and fohii Sidle, who piloted the plane on most flights, were of great assistance. Tienu' Parrish, Gene Maddox, and Kexin (Tlaubius helped gather field data. We are grateful to the landowners in the Platte River Valle\w ho allowxnl us access to tlieir properties; and we appreciate the help of Kenneth and Marie Strom. We also wish to thank Ronald Marrs for his help in inteq)retation of aerial ])hotographs. Funding was proxided b\ the U.S. Bureau ol Reclamation in Cirand Island, Nebraska, and the U.S. Fish and Wildlife Ser- vice National Ecology- Research Center in Fort Collins, Colorado. FlTKHATl'HH ClTI'.l) B()\i:k, K. I). 19S6. Development ami evaluation ol lialntat suitaliilit) criteria for use in the iiistreain How inere- niental niethodologv. U.S. Fi.sli and Wildlife Seniee Biological Report 86 (7). 14 pp. Bl ciiAWN.T. J.. andW. P. Somkhs 1969. Discharge inea- snreinents of grazing station.s. Book 3, Chapter 8A in Technifjiie.s ol'water resource inxestigations. U.S. Geo- logical Sinvey. Washington, D.C. 6.5 pp. BvKHs. C. H.. R.'k. .STKiMiOKST. and I'. H. Kii\rs\i\\ 19S4. Classification of a technique for analysis of utili- /iition— a\ailal)ilit\- data. Journal of Wildlife Manage- ment 4S: 10.50-1 (),3.3. ClIUUKK P. J, 19S2. The lloodplain xegetalion oi the Platte River: ph\tosociolog\, forest dexelopmeut, and .seed- ling establishment. lhipiil)lish(«d doctoral dissertation. Iowa State Uni\ersih. .\mes, .332 pp. Ks( ii\i;k T, H. IIadikv and K. Ckowlkv 1981. Hydro- logic and morphologic chiuiges in the Platte River Basin: a historiciil perspective. U.S. Geological Sunev Report 81-125. Denxer, Colorado. 57 pp. Folk VI. J. 1989. Roost site characteristics of Siuidliill Cranes in the North Platte River ot Nebraska. Unpub- lished master's thesis. Southern Illinois Unixersitv Car- hondale. 58 pp. Folk M. J., and T C. T\(;nA 1990. SantDiill Crane roost site characteristics in the Nordi Platte River \'iillev. journal of Wildlife ,Managenient 54: 480-486. Vh nil C. R. 1974. The ecology of die Platte Ri\'er as related to Sandhill C'nuies and other waterfowl in south central .NebrLLska. Unpublished master's thesis, Keaniev State College, Keaniey, Nebraska. 116 pp. . 1986. Crane habitat of the Platte River. Pages 151-156 in J. C. Lewis, ed.. Proceedings of the 1981 Crane Workshop. Natiouiil Audubon Society, Tavenier, Florida. Kn^ciiEH. J. E.. and M. R. Kahlinokh 1981. Changes in surface-water h\'drolog\' for the South Platte Ri\er in Colorado iuid Nebraska, the North Platte Ri\er and Platte River in Nebraska. U.S. Cieological Sune\' Report 81-818. 77 pp. KnAlH;, G. L. 1978. Siuidhill C'rane use of staging areas in Nebraska. Pages 1-6 in ]. C Lewis, ed.. Proceedings of the 1978 Crane Worksliop. ( Colorado State Uni\er- sitv. Fort Collins. . 1987. Use of staging areas by Sandliill Cranes in the niidcontinent region of North ■\merica. Pages 4.51—462 //( C. W. Archibald and R. F Pasquier. eds.. Proceed- ings of tlie 1983 C]rane Workshop. International Crane Foundation. Baraboo, Wisconsin. KiiM'i G. L., D. E. Fackv, E. K. Fklizkll and D. H. JOHNSON 19S4. Habitat use In migrant Sandhill Ch"aiies ill Nebraska. |ournal of Wildlife M;magement 48:407-117. Kkall G. L, K. J. Rlinl( KK anil C. R. FiUTii 1982. Sandhill CJranes and the Platte Ri\er. Transactions of the North ./Vnierica Wildlife Natural Resource Confer- I'lice 47: 542-.552. Khoonkmkvf.k. K. E. 1978. The U.S. Fish and Wildlife Senice's Platte Ri\'er national wildlife stud\. Pages 29-.32 //( |. C. Lewis, eil.. Proceedings of the 1978 Crane W(jrksliop, Fort Collins. Colorado. LviKA D. C. and j. W. Yaunke 1986. Simulating the roosting habitat of Sandliill Cranes and validation of suitabilih-of-use indices. Pages 19-22 in J. Winer, M. L. .Morrison, and C:. J. R;ilph. eds.. Wildlife 2000: modeling habitat relationships of terrestrial \erte- brates. lhii\ersit\ of Wisconsin Press. .Madison. Li \\ Is |, C. 1974. Ecol()g\' of the Sandhill Crane in soutli- lasteni (.'I'litral Fl\Avay. Unpublished doctoral disser- tation. Oklahoma State University Stillwater. 213 pp. . 1977. Siuidhill Cranes (Gms canadensis). Pages 5-43 //i C. C. .Anderson, ed., Management of migrator)' shore and upland game birds in North .America. Inter- national Association of Fish and Wildlife .\gencies, Washington. D.C. \I\i;( IM C. 1,., ,111(1 I). (). hiiis(.\ MiniA 1980. .\ non- mapping techiiKjuc lor stiuKiiig habitat preferences, journal of Wildlife Mauageinent 44: 96.3-968. I'll Ml lii I I I. M. |. 1988. Measuring channel width \ariables ol S;milliill Crane roosting habitat sites along the Platte Hi\ei using nighttime aerial thermograpln'. Applied Scieiuv R.'lcivncc Memo. No. AD 88-4-5. U.S. Departiiuiil of Interior. Hiirt-an of Reclamation, I )cn\cr, ( Colorado. 19921 CRAM:: HoosT Sites 261 Hki\K( KK K. l.aiuIC L. KhaPL' 1979. Spring food Iiahits of Sandliiil (.'laucs in Nebraska. Pages 13-19 /)( |. ( .'. Lewis, ed.. Proceedings oi tlie 197S (iranc Worksliop. F^oit Collins. C'oloratlo. Siiii.K. J. G.. E. D. .Mii.LKK. and P. J. Clhhii.h 19S9. Changing habitats in tlie Platte Ri\er \'alle\ oi Nebraska. Prairie Naturalist 21: 91-104. U.S. Fish .wn Wh.di.ikk Skhvice 1981. The Platte Ri\er (X()log\ stndy. Special research report. Jamestown, North Dakota. I ST pp. Will, I WIS (;. P 1978. The case of the shrinking channels — the North Platte and Platte Rixers in Nebraska. Circn- lar 781. U.S. Ceological Sur\e\, Reston, \'irginia. 48 pp. Received 6 Drccinher I^J^Jl Accepted :V) }nhi ]UH2 Great Basin Naturidist 52{3), pp. 262-26S POST-PLEISTOCENE DISPERSAL IN THE MEXICAN VOLE {MICROTUS MEXICANUS): AN EXAMPLE OF AN APPARENT TREND IN THE DISTRIBUTION OF SOUTHWESTERN MAMMALS Russell Diuis' cUicl J. R. Calkhan" ABSTR-Kcrr. — The present distribution of the Mexican \ole {Micwtiis mcxicanits) is not entirely the product of post- Pleistocene forest fragmentation and extinction; recent dispersal also is indicated. Literature records further suggest that this phenonient)n nia\- reflect a general pattern of northward lange expansion in many southwestern mauuual species. Kx-i/ iionl.s: Microtns. vole, dispersal, hi()<^e()^i-(ij)liy. vieaiitiitce. Pleistocene. Traditional hiogeographic tlieon attributes tlie niodeni distribution of small, nonll)ing niontant^ niamnials in the Southwest to post- Pleistocene climatic change (Brown 1971, 1978, Patterson 1984, Patterson and Atmar 1986). Restriction of woodland and forest habitat to higher elex^ations is assumed to have stranded sucli species on isolated patches of montane habitat. Although it is recognized that local extinction has caused further range reductions, post-Pleistocene range expansion generalK' has been discoimted( Brown 1971, 1978). This relict model satisfactorih' explains the distribution of many Great Basin species, but evidence from else\\'here in the Southwest strongK' supports recent dispersal (Da\is and Dunford 1987, Daxis and Ward 1988, Da\is et al. 1988, Daxis and Bissell 1989, Daxis and Brown 1989, Lomolino et al. 1989). In this paper we will review exidence indi- cating that manv southwesteni nuunmals — including the Mexican xole and other montane mammals, as well as nonmontane species — have shown a striking northward range shift during the past sexeral decades. For some spe- cies this pattern appears to reflect mildei- win- ters or human influences; for others the trend is harder to explain. If xerified, how e\(M-, this trend presupposes (among other things) a greater dis- persal capability- than is txpicalK attributed to small mammals. DISPERSAL: A BRIKF RK\1E\\ Post-Pleistocene dispersal has been \erified primarily in (1) conspicuous, diurnal mammals such as sciurids and (2) mammals colonizing regions that were previously well sampled by collectors. For species and groups that do not fall into either categorv, the biogeographer is left to interpret broader distribution patterns ancPor small bits of indirect evidence. As an example of the first situation, Davis and Browii (1989) and Davis and Bissell (1989) showed that recent dispersal has significantly altered the distribution of Aberts squirrel iSciunis abciii). Another example involves the duskv chipmunk {Tamias ohscunis), which was absent from Thomas Moimtain in southern Cal- ifornia at least between 1974 and 1976 (Calla- han 1977). Bv 1979 the species had recolonized this peak, which is isolated from the San facinto range bv a lO-mile stretch of semiarid grass- lancPsagebrush habitat (Callahan, in prepara- tion). The second scenario is illustrated bv Davis and Dunford (1987) and Davis and Ward (1988), who found evidence of recent montane colonization by Signiodon ochrog^nathus in a well-studied area of southeast Arizona. Since manv small mammals are not readily trapjx'd and manv localities have not l)een sam- pled extensivc'lv, it is easv for critics to "shoot down" new distribution records on the grounds of inadequate prior sampling. In such cases it is ^ni-piirtiiifiit picall\ nhabits meadows in ponderosa pine and mixed •ouiter forests, but can occup\- pimon-jimiper woodland if suitable understoiv is present Harris 1985, Hoffmeister 1986). 'in Arizona it 'ccurs less often in interior chaparral and Cir(>at iasin desertscrub (Hoffmeister 1986). The late Pleistocene distribution of this spe- ies probably was continuous from the Mexican lateau to the southwest U.S. (Findle\- and Fig. 2. Details ol tlie distribution oi Microtti.s incxicanus in Arizona showing isolated populations and three subspe- cies A, B, and C (modified from Hoffmeister 19S6). Open circles indicate records added b\- Spicer et al. (1985) and Spicer (1987); subspecific relationships of these populations are unknowni. Papago Springs is a late Pleistocene fossil site which includes a tentative record (or this species (Harris 1985). Jones 1962). Harris (1985) (jucstions a fossil record from southeast Arizona that would con- firm this past di.stribution, but the present dis- junct range of the species (Fig. 1) implies its former presence in southeast Arizona regardless of the fossil record. Post-Pleistocene climatic changes fragmented this distribution, and local extinctions in southeast Arizona apparentK' sep- arated the Mexican and northern populations. This scenario is consistent with the historical legacy h\pothesis, but there is also evidence that the pattern has been modified b\ recent dis- persal as disc-ussed below. E\il)i:\(:K FROM Arizona. — The Mexican \-ole now occurs in the continuous forests of central Arizona and on isolated mountains to the south, southwest, and north (Figs. 1. 2). Four populations occm- on mountains connected to the central high countn In pimon-juniper woodland and interior chaparral (Brown and Lowe 1983), through which the species could (lis[)er,se: the Nantanes Plateau, the Sierra Ancha, the Bradshaw Moimtains, and the South Kaibab (Fig. 2). Three other populations occur at sites that are isolated b\- grasslands but 264 Great Basin Naturalist [\V)Iuiiie 52 lOOkm F"ig. 3. Details ol the clistrihiitioii ot Microtiis iiu'xicanit\ in N't'w Mexico and .southern Colorado showing some iso- lated populations (modified IVom Findlev et al. 1975; some data from Hall I9S1). Open eireles indicate records listed bv Finlev et al. (1986). interconnected hy pinNon-jnniper woodland and interior cliaparral: Pro.spect \alle\, the Music Monntains, and the llnala[)ai Monntain.s (Fig. 2). Since -lif iiualapai Monntain.s and Prospect X'alley still contain small ])atches ol' forest, the vole populations at these sites might be Plei.stocene relicts in Forest refugia. Bnt the population in the Music Mountains, a site midway bet\veen the other two, consists of OnK- pinyon-juniper woodland (Sj^icer ot al. 19S5). Tliis habitat interconnects all three l()caliti(>s and is more likely to sene as a dispersal corridor than as a post-Plei.st(X-ene refnginm. The spe- cies was recorded in the Uualapai Mountains in 1923 and in Prospect \'alley in 1913, but it was not found in the Mu.sic Mountains until 1981 (Spiceretal. 1985). When the rate of dispersal exceeds that of extinction, a species should be present on those luontane islands closest to the .source, assuming the species can cross the intenening habitat (Mac.Vrthur andWilson 1967). The distiibution of the Mexican xole in the Southwest generalK fits this model (Fig. 2; Lomolino et al. 1989). In Arizona tlie most closely related i.solate popula- tions occur in geographic jiroximitx (Hofhuc>ister 1986). Recent dispersal is not the onK possible explanation for this pattern, but it is the most parsimonious one; ancient relicts in dissimilar habitats would be expected to show more e\i- dence of di\'ergence after sexeral thousand vears. There is exidence of a recent range expan- sion in northeast Arizona. The Mexican vole was first recorded in the Navajo Mountains in south- ern Utah and northern Arizona in 1933 (Benson 1935). Although this locality seems isolated, since 1986 the .species has turned up at se\eral other sites on Black Mesa in northeast Arizona ( Spicer 1987). These sites fall on a line southeast from Na\ajo Mountain to the southwest foot- liills of the Chuska Mountains. At Black Mesa (Fig. 2) the habitat is pin\'on- juniper, with ponderosa pines and a few Doug- las-firs on north-facing slopes, draws, and other protected areas (Spicer 1987). Again, this is relati\el\' poor habitat for this species, and it seems unlikeK' that the population could have siuvived in isolation for sexeral thousand \ears. Between these sites and Naxajo Mountain is mostlv pinyon-juniper, with narrow strips of northern grassland and Great Basin desertscrub (Browii and Lowe 1983). The Mexican \ole occupies these habitats elsewhere and presum- abl\ can disperse through them. This scenario implies that the Chuska Mountains, now unoc- cupied bv the species (Hoffmeister 1986), will eventualK' be colonized (or recolonized) from the northwest. E\'idenc:e from New Me.mco and Colo- rado.— Findle\et al. ( 1975) suggested that the range of Microtus iiwxicaniis in New Mexico could lia\ e expanded as a result of recent dis- })ersal. In the Sandia Mountains, trapping from 1950 to 1970 re\ealed onl\- M. hn^iicaudus. Mexican xoles were first taken there in 1970 and soon became the dominant species. While the species could ha\e been overlooked earlier, dis- persal from the Manzano Mountains (Fig. 3) is an ecuuilK' likel\- scenario. Until 1 975 these were the northernmost records east of the Rio ( wande Ri\er in New Mexico. The Mexican vole has since been recorded from five sites in extreme northeast New Mexico (Dakjuest 1975, Finlex- et al. 1986). In C>olora(k) the first .specimens were taken in 1956 at Mesa Verde (Rodeck and Anderson 1956). Later the species was found at seven more (Colorado sites (Fig. 3; Mellott and Choate 1984, Finle\ et al. 1986). \ trapping studv in 19921 \'()i.i". DisrKP.SM. 265 'l^vm.l-: 1. Sontlirni inaiiniial sprcics lorwhicli there ise\init(>(ij)\ iit('iial(>iilii/lltits iiivxicdiiiis ^dsiid UdsUd 'onrpatiis mcsolcunis njds.su Idjdcii N throusili E U.S.; N into S .Arizona tniiii \ Nh-xico \ in Texas Now a winter resident in S .Arizona Now a winter resident in S Arizona N in Texas N in .SW U.S. to UtcJi N in .Arizona N in .Arizona; also Texas? N froin S Texas into Okla- homa, ("olorado, Kansas, and Nebraska Limiti'dK NE in Arizona NW in Colorado. N into \\\()niinti. W into Utah N from SE Texas into Oklahoma, and NE in New .Mexico N in the U.S.; through Kansas to Nebritska. and N in Rio Grande \'alle\ in New Mexico N in New .\h'xico .\\\ in .Arizona and N in Texas \arions in .Arizona; N in .New .Mexico into S Colo- rado N\\ in Arizona ;uh1 per- haps in .New Mexico N\\' in Arizona N in Arizona and New .Mexico I Udvardy (1969). McM;uius (1974); Y. Petryszvii (personal communii'ation ! 3; Tavlor and Da\is 0947); Da\is (1960); Da\is (1974); Mollhagen (197.3) H. Sidner (personal communication '. probabK due to humiuiugbird feeders K. Sidner (personal comiiiiinication '. [)rob;il)l\ due to lumnningbird feeders .Spencer etal. (198S) First U.S. record was in 19.55 in SE Arizona (Cock- nmi 1956); 2 1 and 2 1; Mollhagen (197.3) i^uchamiau and Tahnage (1954); Ud\ard\- ( 1969); Humphre\ (19741; Meaneyetal. (1987) 1; lack of records in N (Cochise ('o. until 1976 (Allen 1895, Roth and Cockrum 1976) I3a\is and Bissell (1989'; known dispersal ability' and histon' of ponderosa pine distribution i l^avis and Brown 1989) Diersing (1979); Stangl and Dakjucst (1986); Tavlor and Daxis (1947) \s. Da\is (1974); recent record in Ijuia ('o.. New Mexico (\\. CTannon, personal comuHmicatiouh (^hoate et al. (1990) Cockrum (1952); Mohlenrich ( 1961 ); Jones (1960); Cameron and Spenci'r ( 1981) .Mohlenrich (1961) Davis and Dunford ( 1987); Davis and Ward ( 1988); Da\is et al. (1988); Hollander et d. (1990); Stangl and Dalcjuest (1991) This studv Not reported bv eiirlv explorers (Davis 1982); not recorded in .Arizona until 1892, in extreme S ( HoffincMster 1986); no late Pleistocene record (Harris 19.85. Tabor 1940); Wallmo and Gallizioli (1954): but see Kaufmann et al. (1976) 1; recent records (Hoflmeister 1986) Indian name for peccarv is of Spanish origin (Sowis 1984); rarelv encountered bv early explorers (Davis 1982); no use bv earlv prehistoric cultures (Crosswhite 1984, Sovvls 1984) 266 Ghkat Basin Naturalist [\ olunie 52 1938, and others prior to 1975, found no Mexi- can \-oles near Cimarron, New Mexico, although otlier \ole species were taken (Armstrong 1 972, Findlev et al. 1975). The Mexican vole is now common in tlie area (Finley et al. 1986); dius, the northward range expansion by this species ma\- he continuing into nottfieast New Mexico and southeast Colorado. Discussion and Conclusions The historical legacy hypothesis requires widespread late Pleistocene distribution. The fossil record documents the late Pleistocene presence of Microtus nwxicainis in jouthem New Mexico, adjacent portions of Texas, and (perhaps) southeast Arizona. Despite the admit- tedlv weak fossil record, however, there is no evidence that the species' range formerly included the entire area where populations now exist (Harris 1985). Sex'eral lines of e\idence support post-Pleistocene dispersal lor this species: 1 . Distance as a predictor of pres- ence/absence (Lomolino et al. 1989). 2. Tlu^ clo.se relationship of adjacent Ari- zona populations, isolated bv theoreti- calK' crossable habitat. 3. Its presence in isolated habitats unlikeK to have served as post-Pleistocene refugia. 4. Recent records suggesting dispersal in n(nlh\\'est and northeast Arizona, cen- tral and northeast New Mexico, and southern (Colorado. Although the distribution of the Mexican xole undoubtedly has been influenced by historical events and by local extinctions, it is difficult to ignore the evidence of past and continuing post- Pleistocene dispersal. A reviewer of this paper asked win' the Mex- ican vole and other small mammals took 4()()() years to reach certain localities that w(^ claim were colonized within the past few decades. This point re(juires clarification. First, there have been local changes in \egetation and cli- mate in the Southwest during the past 50 to 1 ()() years, and these conditions max- have favored recent dispersal even though the broader pic- ture has remained constant for some 4000 vears. Second, we do not claim that these recent records represent the//r.sf colonizations by the Mexican vole or other species. Thev are simply the first such events tliat have been recorded in the literature. If these animals were able to cross unsuitable habitat once, then thev could have done so repeatedl)' in the course of centuries. Our suggestion of recent dispersal bv the Mexican vole should be evaluated in the context of a more general pattern involving manv mammal species. Post-Pleistocene dispersal has influenced montane species assemblages throughout much of the Southwest (Lomolino et al. 1989). In addition, we propose a second pattern of recent northward range expansion involving at least 19 North American mammal species, all primarily austral in distributicMi but occupying a wide range of habitats (Table 1). This pattern of northward dispersal is not easily exjolained, and there is unlikelv to be a single causative factor. For some species, the shift appears to result from climatic change and/or habitat modification b)' humans. Alterna- tively, the pattern can be viewed as one smiill, reconiizable northward surtje in a continuincr Holocene c>cle of nortli/south distribution shifts. ACKNOWLEDCMENTS Preliminaiv drafts of the manuscript were read bv R. Sidner, M. V. Lomolino, and E. L. Cocknun. T \'an Devender and an anonvnnous reviewer also provided helpful comments. Some of the fieldwork cited was conducted by R. B. Spicer and C. 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Southwestern Natnriilist 32; 507-508. Mki.lott. R.S.,an(IJ. R.Ciio.ME 1984. ,S'f»m/.s rt/;r;t; and Mkrntiis motjtanus [= nicxicaiitts] on foothills on the Cnlebra Rtuige in southeni Colorado. Southwestern Naturalist 29:" 1.35-137. NloilLFNRicil J. S. 1961. Distribution and ecologx of the hisjiid anil letist cotton rats in New Me.xico. Journal of .\lanunalog\ 42: 13-24. M()LLIIAc;en. T 1973. Distributional and taxonomic notes on some west Texas bats. Southwestern Naturalist 17: 427-429. PvriFRsoN B. 1). 198 1. .Mammalian extinction anil bioge- ographv in die southeni Rockv Mountains. Pages 247- 293 ill M. H. Nitecki, ed.. Extinctions. Universitx' of (Chicago Press. PvriKRSON. B. D.. and W. Aiauk 19S6. Nested sub.sets and the stnicture of insular inaminaliiui faunas and archipelagos. Biokigical Journal of the Linnaean Soci- et\- 28: R5-S2. RoDFCK, II. G., and S. .Anderson 19.56. Sorex meniami and Microtus incxicdiiiis in Colorado. Journal of Mam- malog\.37: 436. Rom. F. L., and E. L. CVx.krlal 1976. .A sune\ of the mammids of the Fort Bowie National Historical Site. In: ("ocknim et al. eds., Survevof the vertebrate fauna I 268 Gkea'I' Basin Naturalist [Noll of Fort Bowie National Site, Arizona. University- of Arizona Project No. 5010-2849-02, spon.sored hy U.S. Park Sen-ice, Project No. CPSU/UA (X)5. SowLS, L. 1984. The i^eccaries. UniversitAof Arizona I'rcss. Tucson. Spenckh, S. C. p. C. CiioiCAiH. and H. W. Chapman 1988. Northward e.\pan.sion of the southern yellow hat. Lasiuni-s cii ochn)90% of the diet. There was no apparent correlation betw een the importance \ alues of exotic species at a site and their importance in Townsend's ground squirrel diets. Kvij uonl.s: .Spermophilus t(n\nsendii, fixxl habits, dictani anali/sis. Idaho, urotuid stjiiirrcls. The Snake Ri\er Birds of Pre)' Area i.s a 243,()()()-ha tract of multiple-u.se shrub-steppe rangeland achuinistered bv the U.S. Biu-eau of Land Management. Towaisends ground squir- rels (Speniu)pliihis townsendii idaltoensis) are important prey of raptors, and continued exis- tence of the area's dense breeding populations of raptors depends upon dense Townisends ground scjuirrel populations (U.S. Department of Interior 1979). hnasion of southwestern Idaho rangeland by e.xotic annuals such as cheatgrass (Broinus tectonun). tumblemustard {SisijDihhuiii aliis- siiiiuni\ pinnate tan.symustard {Descuraiiiia piniuila). and tunil)I(n\-e(Hl (Salsola iheiica) has resulted in trecjueut and destructive wildfires that kill natix e shrubs and weaken natixe bunch- grasses. Oxer time, fires ha\e n\sulted in the permanent replacenu'iit ot luitiw slirul)- and bunchgrass-dominated comnumities b\ e.xotic annual-dominated comnumities (YenscMi 1980. Kochert and Pellant 1986). Townsend's gromid S(juirrel populations are niucli less stable in exotic annual-dominated connnnumities than in natixe shrub communi- ties (Yensen et al. 1992). Native perennial f()d)s, bunchgrasses, and shrubs apparentK' proxide a more constant, stable food soinx-e than exotic annual species that ma\- xan- in producti\1t>' between xxet and dn" xears b\- sexeral orders of magnitude (Young et al. 1987). Like other ground squirrels of subgenus Spenuopluhis. Townsend's groimd s(juirrels eat green xegetation earK' in their fom- to iixc- month actixe .season, then eat seeds of gras.ses and forbs to fatten up for hibernation ( Hoxxell 1938, Rickart 1982). In southwestern Idaho, Toxx'usend's groimd squirrels are in (^stixa- tion/hibeniation from |une or (ulx' until the fol- lowing Januan or Februarx with loxv sunixal rates (ca. 289f ; Smith and lohnson 1985). Food quantitx and cjualitx' could influence oxerwin- teiing surxixal as xx'ell as reproductixe success the folloxxing spring. Toxxnsend's ground s(|uirrels are known to eat natixe forbs {Sphdcnilcca: Daxis 1939 ), bunch- grasses {Pod sp.; fune grass, Kiwlciia sp.; Daxis 1939), and desert shnibs (big sagebrush, Arte- uiisia Iridcntata: budsage, Artemisia spinescens; shadscale, Atriplex coufeiiifolia; Daxis 1939, lohnson 1961), as xvell as in.sects such as grass- hoppers and cicadas, and occasional!)' carrion , Museum of Natural II istorv-. .Mbert.sou College, Caldwell, Idaho 8,360.5. 'Bureau of Land Mauanenient. .3948 Uevelopmeut Ave.. Boise. Idaho 8370.5. Present aildress: Idaho .Xnii\ National Cinard. Department of En\iroinnent. Box 45, Gowen Field. Boise, Idaho 8370.5. 269 270 Great Basin Natuhaljst [W^lume 52 Tabi.K 1. \e2;etation importance values (% relative cover plus % fVeciiiencv) in May 1987 and 1988 at four study sites near Co\ote Butte in the Snake River Birds ofPrev Area, southwestern Idaho. Study Site Bis Nativ e Exotic Rehabilitation Species sagebmsh grasses annuals seeding 1987 1988 1987 1988 198' r 1988 1987 1988 Ghassks 'Broiniis tectoniin 25 2 11 33 86 35 0 31 Poo seen 11(1(1 67 60 90 58 45 45 85 60 Viilpid octojlora 16 "■ 24 0 2 8 12 3 Sitanioii liijstrix 16 11 14 14 8 21 0 28 °.\i)ijron dcsciioni ni 0 0 0 0 0 0 29 0 SlIIUBS Cc rat (7 ides Unuita 29 47 3 5 (1 0 ( 0 Artemisia trideiitafd 33 39 0 0 0 4 0 0 Atni)lex iiitttiillii 0 0 0 0 0 0 0 20 FOKBS "Sdlsola iberiea 0 0 33 26 0 0 40 18 "Descumiuia sopliia 0 0 3, 0 0 0 0 0 'Sistjiiihriiiin (illissimiiin 0 11 8 31 34 14 0 5 "iMctucd serriold 0 0 0 0 0 0 4 0 Other forbs 0 5 0 9 0 ■-) 0 2 Total Co\F.K(%) 35 24 26 15 21 10 18 14 *ex<)tic species (Howell 1938. Alfoni 1940). However, they do eat introcluced clieatgrass, tunihleiiiustard, peppergrass {Lcpkliuiii pcifolidfiiin; Da\is 1939) as well as crop species like alfalfa, wheat, bade\; potatoes, beets, carrots, and lettuce (Howell 1938). Johnson (1980) and Rogers and Gano (1980) studied diets of" Sj)('niioj)liilu.s lowiisciulii townsendii in Washington and found natixe bluegrass {Foa sp., 26-29%) and lupine {Lupinus hixifloais, 11-25%) to be dietaril\- important, whereas Dcscurainin was the onl\- e.\(;tic eaten in quantit\' (15-33%); cheatgrass, tnnibleweed, tuuiblouustard, and peppergrass constituted 0-4% of the diet. Johnson et al. (1977) estimated the percent \-olunie of food categories in 174 Towiisend's ground scjuirrel stomachs in the Snake Ri\-er Birds of Prey Area. They found grasses, including cheatgrass, were most important, followed In forbs and winterfat {Ccnitohlcs laiuila). Because cheatgrass. tuiiiblewced. tinnble- nuistard, and peppergrass are becoming increasingly dominant in the Snake River Bircls of Prey Area, tliis study was designed to leaiii if Townsends ground s(juirrels were substituting these exotics for natixe species in their diets. We also wished to learn if cousnmplion-introdnced plant species increased with increases in the proportion of exotic aiuuial species in the habi- tat. Hf)wever, the studx' was not designed to stud\' dietaiv preference as such. Study Sites Four stud\ sites were located near Go\ote Butte, approxiuiateK' 19 km south of Kuna, Ada Gountx, Idalio, in the Snake Ri\er Birds of Prev Area. The sites described l:)elow were selected for progressively greater dexiation from undis- turbed native vegetation. Unburned big SA(;EBRL)S1I. — This site (TIS. RIW Sec. 24; elev. 850 m) is a big sage- brush-winterfat mosaic and represents the uubunied condition of thc^ other three sites. Big sagebrush, winterfat, and native grasses (Sandbergs bluegrass [Poa sccunda], squirrel- tail \Sit(nii()ii lii/sfrix], and sLx-weeks fescue [Viilpia ()cl()fh)ni\) dominate the site; cheatgrass is the main exotic annual (Table 1). Nvri\ !■: GRASS.— This site (TIS, RIW, Sec. 13; ele\'. 850 m) is <1 km northwest of the unburned big sagebrush site in a former big sagel)rush-wint(M"fat conuiiunitv burned by a human-caused wildfire on 26 August 1983. The fin^ killed thc^ shnibs, and the site was domi- nated subse(juentl\' b\ uatixx- Sandbergs blue- grass, six-weeks fescue, and scjuirreltail, with 19921 TowxsKXDs (iHorxn Soiikhki, Dikts 271 some introduced tuiiil)I('\\('('d. tlicatgrass, and other (Aotic- animals present lTal)le 1 V fclXOTIc AXXIALS— This site (TIS. HIW, Sec. 13; ele\'. 850 ni) is adjacent to the natixe grass site and was similar to it prior to the 1983 burn (13. L. Quinnex; unpnbHshed data). Both sites were bunied b\" the same fire. However, since the fire, the exotic annuals cheatgrass and tumble mustard, with some remnant natixe glasses, especiallx Sandbergs bluegrass (Table 1), haxe dominated the site. RKHABILITATION seeding. — This site is located fi km east, 2.5 km south (TIS, RIE, Sec. 27: elex'. 885 m) of the unburned big sagebnisli site. The area burned in 1981, xxas reseeded with deseit x\iu\itgrass (Ag^ropi/roii desertoniin) in 1982, but burned again in 1983. In 1987 and 1988, tlie area xx'as dominated bx' Sandbergs bluegrass, desert xxheatsrass, tumblexxeed, and other natixe and exotic forbs (Table 1). Methods To determine the degree of exotic annual inxasiou at each site, vegetation analxsis xxas conducted in earl)' June 1987 and late Max' 1988 x\ hile Towiisend's ground squirrels xvere being collected. At each site xve used a transect xxith foitx" 1-m' quadrats spaced at lO-m intenals (Daubenmire 1959). Percent coxer of each spe- cies xx'as estimated using a 1-nr (jiiadrat frame dixided into tiMiths to facilitate estimation. To gixe a better approximation of the axailabilitx of each plant species, percent relatixe coxer and jiercent relative frequencv xx^ere conxcMted to importance values (Cox 1990). Squirrels xvere collected bx tia])ping and shooting at all four sites in Max and June 1987 in = 75) and in March and Max 1988 (// = 42) except from the rehabilitation seeding site in May 1988. Squirrels xx'ere aged in the field using pelage and bodx xxeight ciiteria (Bureau oi Land Management, unpublislied data). Hepre- sentatix-e specimens xxere prepanxl as ( 1 ) stan- dard stiidx skins xxith skulls (/; = 12), (2) skeletons [ii = 3), or (3) skulls only (/; = 25) and deposited in the Albert.son College Museum of Natural Histon. Tooth-xx-ear patterns (Yenseii 1991 ) xx'ere consistent xxith the ase assi";imi(Mits for all specimens. Based on these criteria, all 1987 specimens xx'ere juxeniles since thex xxere collected late in the active season xx'hile the adults xx'ere entering seasonal torpor: all 1988 specimens xx^ere either yearlings or adults. Stomachs xx'ere remoxed from the animals iimn(xliat(^lx- postmortem andpresened in 70% cthaiiol. In the lab, stomach contents xvere remoxed from ethanol, diluted 50% xxith xxater, and homogenized 1 min in a Waring blentler to produce fragments of uniform size. The homog- enate xvas xvashed through a l-mm siex-e (Hansen 1978) and collected in aO.l-mm screen to remoxe tiny, unidentifiable fragments. The material xvas then mounted on microsco])e slides using Hertxvigs and Hoxers media ( Sparks and Malechek 1 968 ). Plant .species in the diet x\er(^ identified bx' compari.sons to a reference collection of micro- scope slides using microhistological characters. All reference slides xx'ere made from catalogued specimens in the Albertson College Harold M. Tucker Herbarium andxx'ere prepared using the technicjue described aboxe. For food habits analysis, one slide xvas exam- ined per stomach. Occurrence of food catego- ries (frequencx') xx^as recorded from each of 20 microscope fields per slide using a phase- contrast microscope at lOOX. Frequencv/20 fields xx'as tlien converted to percent relatixe density' (Sparks and Malechek 1968) using a table dex'ek)ped for fre(juencx-to-densitx con- xersion (Fracker and Brischle 1944). The importance of each dietarxcategorxxxas calculated in three xvays: (1) percent relatixe densitv; a standard dn-xveight conxersion from frecpiency data (Spark's and'Malechek 1968); (2) percent frecjnencx in stomaclis. the percentage of stomachs from a site xxith the item; and (3) percent fre(jnencx' in micr()sco[)ic fields, the percentage of all microscopic fields from a site xxith the item. Txx'entx' microscopic fields xxere examined from each slide using a predetermined pattern, and frequencx' of occurrence of each spt^cies xxas recorded. The frecjuency of each dietarx categon/2() fields on one slide xxas compared xxith other slides (or replicate counts of the same slide) using the Kulcvznski Index (Oo.sting 1956) (also xxell knoxxii as the Brax-Curtis simi- laritx index [Brax- and C>urtis 1957]) 2w/ (a +b) The index xxas calculated as a dissimilaritx index, 1 - [2w/{a + h)] using a BASK' microcomputer program pro- xided bv Ludxxig and Rexiiolds ( 1988). \\'eather data xxere from the National Oce- anic and .Atmospheric Administration monthly 272 CiHEAT Basin Nathhalist [N'olunie 52 Tablk 2. Late season (25 Mav-19 June) 1987 Townsend's ground stjuinel diets. Data are from stomachs of juvenile TGS at four sites in tlie Snake Ri\er Birds of Prev Area. Adults were entering toipor and none were collected during this period. Dietar\- composition is given as percent relative densitv' (RD). percent frequency in microscope fields (MF), and percent frequency in stomachs (PS) for each dietary categor\-. Other s\nil)()ls: + = <17f,- = aiiscut, and// = number of stomachs. Dietar)' categor>- Unbumed big sagebrush RD MF PS Native grasses Exotic annuals RD MF PS RD MF PS 21 GlUSSES Bromu.s tcctonim 22 41 Poa sc'ciinda 24 35 Sitanion liystrix + 2 Oryzopsis hijmcnoides - Grass seed + 5 Grass root? 2 9 Total grasses 49 Siihi;bs Ccratokh's lanala 3 9 Artemisia thdciitata + 2 Atiiplex niitttillii - - Clinfsotlunniitis lisciiliflmus - - Total shrubs 3 FOHHS Sdlsola ihciiai 39 69 Sisi/inhiiiiui (iltissiimiin + + Di'scitniiuia — 2 spp. + 2 Lcpiditiiii pcrfoliatum - - C.njptdttthd intcmtpta + + Rdnitunihis tcsticuldln.s + 1 Ldctucd scrriold Gheno[5odiaceae - - Uuidentilied lorb - - Total fod)s 40 MlSCKLI-ANKOrS Insects S 17 Fungi - - Unknown + + Unidentified seed + I Totiil mi.scelliuieous S 71 Sfi 10 19 10 52 14 91 5 24 5 5 62 20 62 93 19 1 20 44 4 100 + + 5 + 1 5 + )4 2 5 4 5 10 1 3 10 + + 5 40 60 5 20 5 90 10 15 31 45 87 "■ S 40 + + 13 + 1 13 + 3 13 39 43 59 67 6 19 67 2 5 13 51 1 3 20 13 7 21 ST + 1 ■; + 4 7 8 Rehabilitation seeding RD MF PS 19 95 11 57 11 17 32 + ■T 5 4 12 37 + 2 5 16 63 21 21 + 0 21 6 " 11 L8 3 11 53 + 2 5 4 5 5 Idaho (.'limatolopcal Data rcpoit.s lortlic^ Kuna 2 NNE weather station ea. 20 km N oFthe .stucl\- sites. Hksuits Vegetation Analwsis The \egetation at c-ach site (Tal)le I) \ane(l signifieantly from the other sites (all p < .01; H X C G-tests of independenee; Sokal and Hohlf 1981). Using the Knlc\zn.ski lnckv\, the similarity- among the four sites averaged 48.7% (range 27-73%) in 1987. The unburned sage- brush site was more similar (60% ) to the native grass site and less similar to the exotie annual and seeding sites (44 and 47%, respecti\ely). The \egetation at eaeh ot the lour sites \aiied significantly (all p < .01; R x C G-tests of independence) between \ears (Table 1). Importance \aliies axeraged 65% similar (range 48-77%) at a site between years. Total percent coxer decreased on all sites in 1988. In 1988, when thert^ was less herbaceous co\'er, the sites were slightK' more similar (.\ = 61.3%, range 47-74%). Thus, each site differed almost as much beh\'een \ears as the sites differed among each other in a gi\en \ t'ar. 8tomach Anahses Although the three measm-es of dietaiy iin[)()rtance (percent relative densit\- [ = percent dry weight], percent frequency in microscope fields, percent frequency in stoiuachs) gave 19921 TOWNSKXDS (;iU)lM) S()L lUKliL DlKTS 273 (lilfci"iMit iiiiiiu'i'ica] results, the rank orders among ealegories were generalK consistent (Tables 2 — 1). Ho\\e\er, percent frecjuencx in stomachs was \er\- sensitixe to sample sizes. There were 1-9 food cate<2;ories per stom- ach. Site means varied from 3.S to 4.4 categories per stomach. The total numher ol food catego- ries usetl 1)\ all Townsentl's ground stjuirreis sampled at a site \arietl from 4 to IT on the three sampling occasions (Ma\-|nne 1987, March 1988, May 1988). However, if species used in trace amounts (<5% relative densits) are elim- inated, onlv 3-6 (x = 4.0) categories were used per site and onK- 2-4 species comprised >10% ot the diet. Species comprising >l()'yf of tlie diet at one or more stud\' sites included Sandberg's bluegrass, cheatgrass, six-weeks fescue, winter- fat, bio; sagebrush, tumbleweed, Descunibiui spp., seeds of bur-buttercup [Rdiitiiiciiltts tcs- ficiilatus), and insects. Grasses were important constituents of the diet in both 1987 and 1988 and often comprised o\er oiWc of tlie diet (37-889f relative density. Tables 2—4). Sandberg's bluegrass and cheatgrass were both heavih' utilized, especialK in March 1988 (55-87% of diet). Late in the Townsends ground scjuirrel active season (Ma\ and June) use of grasses declined (except at the exotic annual site in 1988). Most of the grass eaten in .\hi\-|une consisted of seeds, especiallv of cheatgrass. Sandberg's bluegrass leaves were utilized slightlv more than cheatgrass leaves (Tables 2-4), and the tvvo together were far more important than all other grasses com- bined. S(juirreltail was little used, altliough it was the third most abundant grass. Winteifat (0-43% relative density ) and big sagebrush (0-21%) were both eaten, and winterfat was especiallv important at tiie exotic site where it was least abundant. Winterfat was utilized at all sites in 1987, even though it was not abundant enough to be sampled 1)\ the vegetation analvsis at the exotic annual site. In 1988 it was eaten onlv at the unburned big sagebnish-winterfat site, and its use declined between March and Ma\' 1988 (Table 2). Big sagebnish was u.sed in March at all sites in both vears but was less important in Max. Tumbleweed and tumblemustard were the most important forb species cc^nsumed. Tans\- mu.stards [Descurainia sophia and D. pimiaia). peppergrass, seeds of bur-buttercup, and leaves of pricklv lettuce {Lactuca seniola) were of secondan importance. All of these are intro- duced annuals. BristK cnptantha (Cn/pfantha inl('rnij)fa) was the onK nati\(^ forb found in Townsends gn)und s(|uirrel stomachs. Altliough 1988 sample sizes were small, the importance of forbs in the diet increased in the samples between March and Mav 1988, while the per- centage of grasses and shnibs decreased (Tables 3-4), thus .suggesting large seasonal differences between March and Nhiv diets. A sm"j)rising number of insects were eaten, especially in Ma\-june 1987 (3-19%; Table 2). However, insects wen^ not important in 1988 (trace amounts at the big sagebrush site onlv). Insect remains were so f ragmentarv that identi- fication was not usuallv possible. However, abundant Lepidoptera lanae could be recog- nized bv the soft e.xoskeleton and prolegs, and fragments recognizable as beetle antennae and t4\tra were found. The importance values of exotic species were lowest at the unburned big sagebrush site in both vears and highest in the exotic annual site in 1987 and at the native grass site in 1988. However, there was no correlation between the importance values of all exotic annuals at a site and their importance in the diet at that site (r = -.454; Tables 1-4). Di.sc.'us.siox Th(^ data show tliat lor sites with varviug degrees of exotic annual invasion sampled over a tAvo-v(\u' period, Tovvnsend's ground scjuirrels can and do utilize introduced species in their diets, and that cheatgrass. tumbleweed. and tumblenuistardare the most impoitantof the.se. Both the vegetation at a site and Tmnsend's ground squirrel diets varied considerably between years and among sites. Differences in amount of precipitation most likelv account lor the differences in vegetation importance values betA\-e(Mi vears. There was less September-Muv pi-ecipitation ( 192 nun in 1986-87 and 170 nun in 1987-88 at Kuna ca. 20 km \). The Daubenmire (juadrats were taken on the same transect in botli vx^ars bv the same technicians. The substantial annual differences in Townsends ground scjuirrel diets may be the result of (1) vegetation differences between vears. (2) the fact that juveniles were sampled in 1987 and adults and vearlings were collected in 1988, (3) differences in collecting dates (25 Mav-19 June 1987 versus 16-19 Mav 1988). or (4) small .sample sizes. 274 Cheat Basin Naturalist [Volume 52 TA151.F. 3. EarK' season (March) 1988 Towjiscnd's ground sciiiirrel diets. Data are from stomachs of achilt and yearling TCS at four sites in tlie Snake River Birds of Prey Area. (Ju\eniles were not a\ailahle in March.) Dietaiy composition is given as percent relatixe den.sitv' (RD), percent fre(iuency in microscope fields (MF), and percent frequencx of stomachs (PS) containing each dietaiT categoiy. Otlier. symbols: + = oIumbian (S. cohinihidims) groiuid squirrels. On the other hand. Hie 19SS data do show a strong seasonal component. Thus, the obsened annual dietan differences may be a result of later collecting dat(>s in I910% to the diet. Rogers and Gano (1980) found duit onl\ three plant species [Poa spp., Dcscurainia piiiiKifa. and Liipiniis laxiflonts) contributed >]()'/( of the di(^t of Townsend's ground squir- rels in southeastern Washington. Hansen and Ueckert (1970) found 1-.5 species contributed >10% in the di\erse (47 plant species) diets of 276 Great Basin Naturalist [\'olume 52 WVoming ground squirrels in Colorado. Hansen and Johnson (1976:750) concluded that Richardson [=\\Vomiiiscril)ed the flora and fauna of sewral northern desert biotic coniniunities in Tule \alle\-, located 80 km west of Delia, Utah, in Millard Countv of western Bonnexille Basin. His study durintj; 1939 (June to September) and 1940 (.'Vpril to September) included a descrip- tion of greasewood {Sarcohatiis vcniiicidatiis) and pickleweed {AUenwlfea occiclentaUs) com- nnuiities. From 1980 through 1991 while in ven- torxing the acpiatic habitats of Tule Valley, I noted the axifamia utilizing wetlands, springs, adjact^nt greasewood and pickleweed commu- nities, and saline flats. This note reports on the a\ifauna oc-curring within the two communities and compares the 1980-91 faunal lisitng with that reported prexiously by Fautin (1946). Com- parisons are also made with Fish Springs National Wildlife Refuge, located 50 km north of the Tule Valle\ springs. This study identifies changes in raptors and songbirds that ha\e occurredoxer 40 years and notes the differences bet\yeen natural springs and wetlands and those dedicated to waterfowl management. Description of tiik Tiii.k \'alley AgiATIC EN\ IHONMKNTS Within the greasewood and ])icklc>weed connnunities of central Tule Valle\ are some 25 tissure-fault springs and associated wetlands. Saline flats coxered in part by water from saline seepage springs occiu" to the east and west of these fissiu-e-fault springs. The springs-wetlands yar\- in si/.e from 100 nr to o\er 97.000 nr (Coyote Springs) with a total of 195,000 nr. Couductixity oltlie aquatic sxstems \aries from 1200 (spring .sources) to greater than 93.000 umbos per cm (some wetlands and saline- ponds). Tln"ee-comered bulrush (Sciiyiis aincr- ic(inus) and salt grass [Distichlis spicata) are the dominant emergent species, with Phra presence of trec^s and buildings, and tlie proximitA' of the springs-wet- lands to the momitaiiious Fish Springs Range. Tule N'allev springs-wetlands are nndexeloped and lack the man-made features. An additional factor that mav contribute to the (hfference in a\ifauna constitnencx of Tule \alle\- and Fisli Springs is the contribution over man\' \ears of field ornithologists at Fish Springs National Wildlife Rehige. Two birds. Western Sandpiper and Lincoln's Sparrow, ha\e not been reported in this region in the Latilong study (\\iilters and Soren.son 1983); and the Lincoln's Sparrow was not reported at Fish Springs (U.S. Department of the Interior 1988). Fish Springs and Tule X'allev are in the same Latilong region, and Fish Springs olisenations o\en\'helm the Tule \'alley obsenations within the Latilone studw CONCMA'SIONS A listing of the axilanna lor central Tule \"alle\ is reported. Comparisons are made to the axifauna List reported b>' Fautin (1946) and to the species list prepared b\- the Fish Springs National Wildlife Refuge. Dillerences in spe- cies are noted and explanations are offered. Tablk 1. Distribution of birds in the grea.sevvood-wetland coinmunitv of Tide X'alle' Month of YeiU" J M M J J O N D Specific date.s°° PoniC:il'KDlDAK Pied-billed Crebe Podircps tii'^ricoUis Eared (irebe PodiUjinhus an riliis ' \kdkidak American Bittern Bdtaunis lcritian\asback Ai/tlu/a valisiuciia Redlif-ad Aijtlii/a aiiwricana Merganser Mcrt^its sj). Ruddy Dnck Oxyti ra jainaicensis Caihahtidaf. "Turkey X'ultnre Catliaiics aura Acc;iPirHinAK "Northern Harrier Circus ci/anciis °Sliaq>-shimied Hawk Accipitcr striatus "('ooper's Hawk Accipitcr coopcrii "Swaiiison's Hawk Butco swainsani °Red-t;iiled Hawk Butco jainaicensis Rongli-legged Hawk Butco la'onimon Ra\cn Corvius corax Trocu.ody'iidae Miirsh Wren Cistothnriis palustris I MUSCICAPIDAI': Mountain Bluebird Sialia cumicoidcs MiMIDAK "Northern Mockingbird Mimiis pahjolottos *Sage Thrasher Orcoscoptes inoiitanus ViOTACILLlDAE American Pipit Anthus ndwsccns -AM I DAE . "Loggerhead Shrike Lanius bidoviciamis 1 1 281 Month of Year ] ^ ^ ^ ^^ ] JA S O N D Specific dates" 8/21/87 4/20/86 4/20/86 XXX X X X X ^ X X X X X X X X 10/25/81:12/6/81 '^ X X X X X X X X X X 8/8/81; 6/13/82 9/19/81 X X X X X X X X X X X X X X X X X X X X X X 8/24/81 X X X X X X X X 282 Table 1. Continued. Great Basin Naturalist [Volume 52 Montli of'Yeiir J FMAMJ J ASOND Specific dates" ° Stuhmdaf. Starling Stunuts vulffiris Kmbkki/idak "Yellow Warbler Dcndroica petechia "Yellow-nimped Warbler Dendroiai roroiiata Palm Warbler Dendroica pal mam in "Common Yellowthroat GeothUjpis trick as "Yellow-breasted Chat Icteria vireiis "Green-tailed Towhee Pipilo chloninis American Tree Sparrow Spiz-(dla arhorea "Brewer's Sparrow Spizella hreweri °\'esper Sparrow Fooecefes ^raininrii s Lark spiirrow Cfiondcstcs iJ^ratnmacHs "Black-throated Sparrow Amphispiza bilineata "Sage Sparrow j Amphispiza belli "Lark Bunting Calamospizd melaiioconis Sa\annah Sparrow Passerculus sandtcichensis Fox Sparrow Passerella iliaca "Song Sparrow MeU)spiza melodia Lincoln's Sparrow Melospiza lincolnii "White-crowned Sparrow Zonotrichia leucophnjs Junco Jiinco sp. "Red-winged Blackbird Afifilaius phoeniceiis Western Meadowlark Stumella m'^lecta "Yellow-headed Blackbird Xanthocq)haltts xanthocephahis "Brewer's Blackbird Enpha'^us cijanoeephalus "Brown-headed Cowbird Molothnis ater FKrNCll.l.lDAF, American Cokhincli Carduelis tristis Passkkidaf. House Sparrow Passer doinesticus 2/21/8L3/7/81 9/19/81 9/16/80; 12/6/81 9/20/81 5/2/S7 10/20/90 12/5/81 4/4/81 12/6/81 10/25/81 •Identified \n FaiKin (1946), •"Dates in right c-oliiinn are for t%vo or fewer obser\ations. 19921 Notes 283 ACKNOW LEDGMENTS 1 wish t(j thank Da\ id E. )()\ irm" and C."Ia\t()n M. White for reviewing the niannscript and tor snhsecjiient discussions. References Bkiii.k W. II.. E. D. .SonKNSKN aiulC. M. Wmitk 1985. Utdi birtls: a revised checklist. Occasional Fuhlication #4. Utah Museum of Natural Histon-, Salt Lake Cit\. 108 pp. F.\L TIN. R. W. 1946. Biotic communities of northern desert shnib biome in western Utah. Flcolos^ical Monographs 16:251-,31(). Pi;i KK.SON, R. T. 1990. ,'\ field guide to western birds. Houghton Mifflin Co., Boston. 432 pp. U.S. Dkpahtmknt of i'iik Intkhioh 1988. Birds ol the Fish Springs National Wildlilc Heluge. Dug\va\', Utah. RFfi-6553i-2. W.M.TK.HS. R. E.. ;uid E. Sokknsf.n, f.ds 1983. Utah bird distril)ution: Latilong study 1983. Utdi Division of W ildlife Resources Publication 83-10. 97 pp. Received 10 yovcniher imi Accepted 22 jiuw 1992 Great Basin XatimJist 52(3), pp. 284-287 WILDFIRE AND SOIL ORGANIC CARBON IN SAGEBRUSH-BUNCHGRASS X'ECETATION Ste\'en A. Acker Kc'ij words: soil organic matter, soil organic carbon, wildfire, big sagebrush. Artemisia tridentata wyomingensis, Artemisia tridentata tridentata, Imnchg^rass, long-term site degradation, Oregon. Soil organic matter is an important compo- nent of the enxironment for plants, one that enhances a\ailabilit\' of water and nntrients (Nelson and Sonnners 1982), contributes to a siiitai)le seedbed ( Monsen and McArthur 1985), and enhances seedling emergence (Wood et al. 1978K In the sagebnish region of the Inter- movmtain West, loss of organic matter due to recurring wildfire may be a mechanism of long- term site degradation, ultimateK' caused b\ excessixe li\estock grazing and the introduction of aggressixe annual plants (West 1988). Loss of organic matter or plant co\er due to fire ma\' increase erosion and decrease infiltration, therein' decreasing seedbed quality' (Monsen and McArthur 1985). Loss of organic matter ma\- also render soils less friable and more likel\- to form crusts upon drving, and so increase the resistance emerging seedlintrs nuist o\ercome (Wood et al. 1978). On the other hand, it is concei\able tliat the increase of the introduced annual cheatgrass {Bromiis tectonim L.) that mav follow wildfire (West 1988) iua\- increase soil organic matter over the long nm, due to litter accumulation. Documentation of the response of soil organic matter to wildfire in the sagebnish region is limited. On relatixeK mesic big sagebrush {Artemisia tridentata Nutt.) sites, tlie occurrence of a single fire apparently does n(jt decrease organic matter in the siuface soil layers (Nimir and Payne 1978, Humph re\ 1984). This study concerns the effect of wildhre on soil organic matter in relatively xeric big sagebrush sites (Acker 1988). Methods I studied soil organic matter at two ptiirs of burned and adjacent unbumed big sagebrush- bunchgrass stands in northern Hamev Countv', Oregon, USA. The stands were selected along with se\en other pairs for a stucK of post-wild- fire big sagebnish-bunchgrass vegetation dynamics (Acker 1988). I selected as study stands bunied and adjacent unburned areas in which at least one of four climax bunchgrass species was present (bluebunch wheatgrass, Agropyron spicatum [Pursh] Scribn. & Smith; Indian ricegrass, Onjzopsis Jn/menoicles [R. & S.] Kicker; needle-and-thread, Stipa comata Trin. & Rupr.; and Thiu'ber's needlegrass, Stipa thurheriana Piper) (Hironaka et al. 1983). The climate is semiarid (28.9 cm annual precipita- tion on axerage for Bums, Oregon, about 40 km north of the study area), with hot, dn' summers and cold winters (Franklin and D\niess 1973). Soils are stony and shallow o\er lava or welded ash deposits, and are classified as Lithic Xerollic Haplargids mixed with Lithic Torriorthents (Lindsax et al. 1969). Within pairs, the sites are similar in elexation, slope, aspect, and surface soil texture (Table 1 ). Other than incidental use, none of the four stands was grazed b\ domestic livestock during this stud\ oi" o\er sexeral decades (M. Armstrong, personal communica- tion). Shrub skeletons were present on all the bunied stands. Thus, prior to the recent fires, ])aired stands probabi) had similar fire histories. The initial wildfire occurred in August 1981. The stands were sampled in the earlx' summer D<-partmeiit of Bolanv. Uiiivt'rsit\ ofWisconsni-Madison, M.ulison. Wisconsin 53706 l>ivsi-iit .uldivss Drpartinent c.f Forest Scit-nce Collese of Forestry, Oregon State Universit)-.Corvallis, Oregon 97331. 284 19921 Notes 285 Tablk 1. Enxironmental. historical, and \egetation data for burned (odd numbers) and adjacent unbumed (e\en numbers) bis^ sas;ebnish-bunchgrass stands, IIarne\- Coinih', Oregon, USA. Soil texture determined b\' method of" Liegel etal. (1980)^ Stand number Kiev. (m) Aspect categorv"' Slope Soil texture, top 10 cm Dominant plant species (1985)'' 1 1325 9 17 siuidv loam 2 1325 8 12 sandv loam 3 1360 3 19 loamx- sand 4 1360 2 22 loam\- sand BRTE, ERFI. POSE, PHHO, ORHY ARTRW, PHIIO. ASFI BRTE, STC02, CH\I ARTRT, BRTE,CHNA "1 = SSW; 2 = S.SW; 3 = SSE,VVS\V; 4 = SE,\V; 5 = ESE.VVNW; fi = K.NW: 7 = ENE.NNW; S = NE.N; 9 = \NE (baseil o.i .Vli.lr and Lotaii 1985). Categories 1^ are wanii a.spects; categories 5-9 are ccxil iispects. Plants vsitli at le;ist 3% co\'er, in descending order .\RTRT = Aiiiiidxia tridcnInUi ssp. triikniata. ARTRW = Artcinisiu Irideiitata ssp. wijomiiigcnsls . ASFI = Astragalus tilipes; BRTE = Bwmm tectoninu CHNA = Cltnjsutltamnus naiiseosiis ssp. aUiicaulK; CUVT = Chn/sotlwmmis tiscUliJlortis ssp. visddiflimts. ERFI = Eriaenm fihfolius: ORIIY = Orijzopsis htjmeiwidcs . PHHO = Phhx Iwodii; POSE = Pua sccuiida; STC02 = Stipa coinata. \oiiclier specimens on Pile at University of Wisconsin — .Madison I lerbariuin. Table 2. Comparison of organic carbon in top 10 cm of soil in burned and adjacent unbunied big sagebrush-bunchgrass stands, northern Hamey Count\', Oregon, USA. X'alues are mean percentages of mass of oven-dried .soil (standard errors in parentheses). Sttmdard errors were computed using each stands variiuice for 1987 and the number of subsamples for the vear listed (Petersen and CaKin 1986). The number of degrees of freedom for all tests is 30 (E. Nordheim, personal communication). Result of two-tailed t test. \'ear Organic carbon N burned \s. unbimied Stands 1 ; ind 2 1985 burnetl: 1.19(0.24) 3 .4 > P > .2, NS^' unbumed: 0.83(0.23) 3 1986 burned: 1.17(0.21) 4 P > .5, NS unbumed: 1.34(0.20) 4 19S7 bumed: 1.31 (0.10) 16 .4 > F > .2. NS unbumed: 1.15(0.10) 16 Stands 3 ; uid 4 19S5 bumed: 0.63(0.17) 3 P > .5, NS unbumed: 0.68(0.16) 3 19S6 bumed: 0.60(0.15) 4 P > .5, NS unbumed: 0.65(0.14) 4 1987'' bumed: 0.83 (0.07) 16 P > .5, NS imbumed: 0..S4 (0.07) 16 ■'Not significant ''Both stands 3 ai d 4 bumed between the 1986 and 19S7 samplings. of" 1985, 1986, and 1987. Stands 3 and 4 hnnunl again in a wildfire September 1986. I collected samples from the top 10 cm of soil, 3 samples per stand in 1985, 4 in 1986, and 16 in 1987. In the first two years sampling l(K'a- tions were laid out in a systematic manner. In 1987 samples were collected in a stratified random manner. The randomization for tlu^ only remaining unburned stand, stand 2, was further restricted so that the area under slirub canopies was sampled roughK in proportion to the co\er of shrubs in the stand. Shnibs can nfluence spatial patterns of soil chemistry in big sagebrush yegetation (Doescher et al. 1984). Organic matter of the soil samples was issessed using the \Valkle\- Black rapid dichro- matc oxidation mctliod of organic carbon deter- mination (Nelson and Sommens 1982). I used the standard correction factor of 1 .3 to adjust for organic carbon not oxidized in the procedure. Giyen the uncertain (juantitatixe relationship betxyeen soil organic carbon and soil organic matter, I report soil organic carbon, as Nelson and Sommers recommend (1982). I used two-tailed / tests to compare organic carbon betxxeen [)aired stands ( Sokal and liohlf 1981). For 1985 and 1986 I used the .sample \ariance from the 1987 obserxations and the sample size from the year in f|uestion to deter- mine the denominator ot (lie test statistic (Petersen and Calyin 1986). This wius done due to the larger sample size and the (stratified) 286 Cheat Basix Naturalist [Volume 52 random arrangement of the 1987 samples (Greig-Smith 1983). In the strictest sense, these observations can onI\ establish clifferenees between adjacent stands. .Applying these results to burned and unburned big sagebrush- bunchgrass stands more generally is tenuous, due to die lack of replication (Ilurlbert 1984). RF..SU1TS AND DiSCUS.SION For both pairs of stands there was no signif- icant difference in organic carbon in the top 10 cm of soil in any of the three years (Table 2). None of the individual comparisons is sugges- tive of such a difference (P > .20 in ail cases). Although I did not test statistically for a tempo- ral trend, soil oi-ganic carbon does not appear to ha\e changed oxer the course of the studv in any of the stands. Thus, the recurrence of fire at stands 3 and 4 does not appear to have altered soil organic carbon. Changes in organic matter are b\^ no means the onK' ecologically important soil changes wildfire may cause in big sagebrush vegetation (e.g., increa.se of organic acids in burned soil; Blank and Young 1990). Furthermore, the short duration and small sample size limit the gener- alitv of conclusions. However, these stands are not unlike others in the general \icinit)' where climax buuchgrasses persist (Acker 1988). In addition, tlie.se stands offer a rare opportunit\- to obsene l)i', and D in Fig. 1). One of these entrances had an asso- ciated mound. Remaining entrances opened into semicircular pits approximateK 0.6 m in diameter. No material had been transported from below the surface or from tlie surrounding surface to form a crater, as constructed bv black- tailed prairie dogs iCi/n())tu/.s hidoviciaiuis) (King 1955, Cincotta 'l989). All entrances. except the mound, were filled with loose soil. The main entrance descended from one end of an oN'al mound 1.5 m long, 1.2 m wide, and 0.2 m high at an angle of 70° for approximately 0.5 m and lexeled off at a depth of 0.4-0.5 m. Tunnels connecting entrances measured 80- 220 mm High and 80-200 mm wide and were approximately circular in cross section. These connecting tunnels were all within 0.5 m of the surface. A tunnel leading to the nest chamber descended further. Turning bavs, as described by Scheffer (1937) for black-tailed prairie dogs, were found near one entrance, D (Fig. 1). The nest chamber tunnel descended from an entrance without a mound (D in Fig. 1). A side tunnel connected to the mound. After branch- ing, the tunnel gradually descended to a maxi- mum depth of 1.25 m. Another branch, closer to the nest, appeared to rise and was not e.xca- \ated due to time constraints. The tunnel lead- ing to the nest chamber was 1 15-150 mm wide and 105-225 mm high. In front of the nest chamber were three small chambers, 190-350 mm long and 100-225 mm in diameter. One of these chambers, 350 mm before the nest cham- ber, contained old fecal material. \\'hitehead (1927) reported a feces-filled chamber in a black-tailed prairie dog burrow and suggested prairie dogs used it to avoid drowning. The present burrow svstem, however, had no provi- sion to trap air if submerged (Foster 1924). Other chambers near bends in the tunnel may ha\e permitted animals to pass one another. No stored food was found in an\' chambers. An enlarged chamber was located at the end of the bin-row svstem. This chamber had a (k)med ceiling, a bowl-shaped floor, and mea- sured 2 10 nun high bv 210 mm wide b\-25() mm long, (contained within the chamlxM^ was a mass of dry; well-chewed plant material, primarily Dfp.irtii)eiitofSv.vt<'nKiticsiimlEcolog\-, Universih' of Kansas. Lawrciice. Kansas 6604.5-2 KKi Pn Crtifs. WorccsUi . M.LSs.iilinsctts 01610-2.39.5. • 15410 Helen. Sontlinalc .Miclnfrui -18195. lit address: Department of Biologv. College ol the llolv 288 19921 NOTKS 289 TOP VIEW AcKXow i.i;i)(;mk\t.s This research was supported in part by grants tioiii tlie University of Kansas General Research Fund to K. B. Armitage, the IJnixcr- sit)' of Kansas Department of Systeniatics and Ecolog)', tlie Theodore Roosevelt Memorial Fund, and Sigma Xi. The U.S. Fish and Wildlife Senice kindly permitted work on the Ara})aho National Wildlife Refuge. We thank E. C. Patten and J. Solberg for assistance in locating suitable prairie dog stnd\ colonies. The manu- script was impro\ed b\ the connnents of an anonymous reviewer. SIDE VIEW Fig. 1. Structure of excavated white-tailed prairie dog burrow. Capital letters indicate entrances to the burrow system. The nest chamber is indicated h\- a solid star The location of a feces-filled chamber is indicated h\ a solid triangle. Turning bays are indicated b\ t]>. grasses. This was probabK- a nest chamber and not a food storage area because the plants found were not preferred food plants (Kelso 1939, personal obsenation). Se\eral small out- pocketings were found off the nest chamber. Wliile the nest chamber and adjacent chambers and outpocketings superficially resembled a "maternit}^ area" as described by Burns et al. (1989), this burrow had no known use as a maternit)' burrow in three years prior to e.xcaxa- tion. It did, however, resemble deep, permanent swstems described b\- Egoscue and Frank (1984). Within the nest materials were skeletal remains and an eartag of a subadult female wlio hibernated in 1987 and was not resighted in 1988. Average frost depth in this area is betsveen 500 mm and 1 m (X'isher 1945), just abo\'e nest chamber depth. Ju\enile males who used this burrow as a hibemaculum in 1988 were not resighted nor were their remains found. LiTER.ATURE CiTED Bluns. J. A.. D. L. Ki.ATH anil T W, Clark 19.S9. On the stnicture and function of white-tailed prairie dog bur- rows. Great Basin Naturalist 49: .517-524, Clahk T W. 1971. Notes on white-tailed prairie dog {Ctjti- oiiu/s Icuninis) burrows. CIreat Basin Naturalist .31: 11.5-124. . 1977. EcoIogN' and ethologx ol the \\ hitc-tailed prai- rie dog {Ci/noini/s laicttnis). Milwaukee Public Museum Publications in Hiolog\ and (;eololog\- .No. .3. 97 pp. ClNCxrrTA. R. P. 1989. Note on mound architecture ot the black-tailed prairie dog. (Jreat Basin Naturalist 49: 621-62.3. EcoscuE H. J., and E. S. Fkank 1984. Burrowing and denning habits of a captive colonv of the Utah prairie dog. Great Basin Naturalist 44: 495-498. FosTEH, B. E. 1924. Pro\ision of prmrie-dog to escape drowning when town is submerged. |ourual ot Mam- malogN' 5: 266-268. Kkiso, L.'H. 19.39. Food habits of prairie dogs. USD.\ Circular No. 529. 15 pp. Kixc. J. A. 1955. Social behavior scK'iiil organization, and population d\namics in a black-tailed prairie dog towii in the lilack Hills of South Dakota. C^ontribntions from the L;ib()rator\' o( Wrtebratc Biologw No. 67. Uni\er- sit\' of Michigan, -\mi \rbi)r. 12.3 pp .ScHEFFKH. T. M. 19.37. Stu|)artiiieiUofFislK-ric-saiKl\\'jkllirc.Ulali State L.'TiiMMsitw l.imaij, i:ialiS1322 "Present adclrcs.s: Institute of Political Kcoiioniv. Utah ■ Present ailelress: Box 26. La Barge. W'yoniinji S.3I2;3. 290 1992J Notes 291 was iiitennediate between hpical wliitetails and h pical mule deer, and the eolor of the metatar- sal tuftwasprimaiiK w liite. Their tails appeared to he slifj;htl\ l()ni:;er than normal whitetail tails and were i)ro\\ n mer(l and anaK'zed using the General Linear Models (GLM) routine available on SAS. The mock'l used was a 2 x 2 factorial design, with burn treatment (burned, unbumed) and tissue t\pe (bud, twig) as main effects. Clone was used as the error term for the bum treatment main effect. Tissue differences were also examined separateK' for burned and imbunied areas because of a significant burn treatment x tissue interaction. Results Deer use at the Lin{k)n sites averaged 10.7 cm for both btmied and unburned clones (Table 1). Individual twig use \aried wideK; ranging from 1.5 to 33 cm. Although mean use at the two Lindon sites was the same, the burned area had a greater proportion of small bites than the unbumed area (Fig. 2). Over 24% of the bites were in the 1.5-5 cm category at the bumed site as compared to 5.7% in this category' at the unbumed site. Also, a smaller percentage of marked twi^s was browsed in the bumed area (Table 1). Mean use at the Pleasant Grove and Hobble Creek sites during the milder 1988-89 winter was somewhat less than at the Lindon sites, averaging 7.7 and 6.3 cm, respecti\el\ (Table 1). ' Residts from the nutrient anaKsis of sam- pled tissues arc gixcn in Table 2. Main effects from the anaKsis of \ariance were all highly significant. Post-burn sprouts contained more crude protein and phosphorus and were more digestible than unbumed samples. Bud tissue exceeded stem tissue in all three measures. The interaction term was also highly significant for crude protein and phosphoms (p < .0(X)1 and p = .0021, respecti\ely). Runningseparateanal- \scs for bumed and unburned areas revealed that the difference between bud and stem viilues was greatest for post-bum sprouts, creat- ing the significant interaction term. Bud and 296 Great Basin Naturalist [\'olume 52 Lindon burned Lindon unburned 2 ♦ 6 8 10 12 14 16 18 20 22 > 23 Hobble Creek 8 10 12 14 16 18 20 22 > 23 2 4 6 8 to 12 14 16 18 20 22 > 23 Twig utilization (cm) Fiii;. 2. I^istrihiition of stem utilization at Four oaklmisli stutK' sites in Utah Countw Utiili. TaBLF. 2. Attained significance \alues from anakses of variance for nutrient content of Cambel oak. Source of variation Cnide protein Phosphonis Digestibility- Bum treatment 0.0001 0.0002 0.0001 Tissue tvpe O.OOOl O.OOOl 0.0001 B\im X tissue 0.0001 0.0021 0.3519 Clone 0.0001 0.0228 0.0015 twig values from bunied clones differed signif- icantly for all three \ariables (Table 3). Bud and twig values from unburned clones differed onl\ in nitrogen content. Twigs from burned and unbunied clones also differed in appearance, burned t^vigs being more slender at 1 cm (1.ur- luil of Wildlife Management 13; 314—315. . 1950. Feeding deer on browse species during winter. Journal of Range Management 3: 130-132. . 1952. Food habits ot mule deer in Utah. Journal of Wildlife Management 16: 148-155. . 1957. Nutritive value of some browse plants in winter. Journal of Range Management 10: 162-164. Smith. A. D., and R. L. Hubbard. 1954. Preference rat- ings for winter deer forage from northern Utah ranges based on browsing time and forage consumed. |()imial of Range Management 8: 262-265. Stevens. R., and J. N. D.wis 1985. Opportunities for improving forage production in the Gambel oak tvpes of Utiili. Pages 37— il in K. L. Johnson, ed., Proceed- ings of the third Utah slinib ecology- workshop. College of Natural Resources, Utah State Universitv, Logan. In ley J. M. A., AND R. A. Terry 1963. A two-stage tech- ni(jue for in vitro digestion of forage crops, [ounial of die Briti.sh Gra.s.sland SocietA' 18: 104-1 11.' TiKMENSTElN. D. 1988. (ptiercus omnlu'lii. In. Fischer, W. C., compiler. The fire effects information svsteni [data base]. USDA, Forest Senice. Iiitermountain Research Station, Intermountain Fire Sciences Labo- ratorv', Missoula, Montana, magnetic tape reels: 1600 bpi, .'XSCII with Gommon LISP present. Urness. P J., D. J. Neff.and R. K. Watkins 1975. Nutri- tive value of mule deer forages on ponderosa pine summer range in Arizona. USDA Forest Seivice. Rock-\ Mountain Forest and Range E.xperiment Sta- tion, Fort Collins. Colorado, Research Note RM-3()4. 6 pp. Welctl B. L., E. D. Mc:Arthl'r. D. L. Nelson. J. C. Pederson. and J. N. D.AVIS 1986. 'Hobble Greek" — a superior selection of low-elevation mountain big sage- biii.sh. USDA, Forest Service, Intermouiit;un Research Station, Ogden, Utali, Research Paper INT-370. 10 pp. Welch, B. L., J. C. Pederson. and W. P. Clary, 198.3. Abilit\' of different rumen inocula to digest range for- ages. Journal of Wildlife Mtmagement 47: 873-877. Winward. A. H. 1985. Perspectives on Gambel oak niiui- agement on national forests of the Intermountain Region. Pages 33^35 in K. L. Johnson, ed.. Proceed- ings of the third Utah shrub ecologv workshop. College of Natural Resources, Utah State Universitv, Logan. Received 9 March 1992 Accepted 18 October 1992 Great Basin Naturalist 52(4), pp. 3()()->3().S BOTANICAL CONTENT OF BLACK-TAILED JACKRABBIT DIETS ON SEMIDESERT RANGELAND Tcliouassi Wansi', Rex D. Pieper"' , Reklon F. Beck", and Leigh W. Murray Abstract. — Botanical content of black-tailed jackrabbit diets was determined by niicrohistological examination of fecal samples collected from si.\ different vegetation tyjies in sontheni New Mexico on three dates. Grasses comprised the largest component of the jackrabi)it diets, with dropseed species (Sporohohis spp.) and black grama (Bontcloua eriopoda) die most abundant grasses in tiie diets. Leatherweedcroton {Crotoii pottsii) and siJverleaf nightshade (So/c/jn/zu t'laeagnifolium) were important lorbs on most vegetation t)pes. Diet composition vaiied in response to season and vegetation t\pe. Grasses were important during the sinnmer growing season, wliile forbs were selected during their growing season (summer or winter-spring). Sln-ubs were less abmidant in the diet than grasses and forbs. Krtj uonis: inicroliisloloiiicdl iniali/sis. fecal inuili/sis. Lepus califomicus. Black-tailed jackrahbits (Lepus califomicus} are widely distributed in western and central North America. Thev range from Canada sonth- ward to the states of Sonora and (chihuahua, Mexico, and from the Pacific coast eastwaixl to the Great Plains (Hansen and Flinders 1969). Because of this wide distribution, jackrabbits encounter a \ariet\' of potential food sources (McAdoo and Young 1980). Considerable work has been conducted on food habits of the black- tailed jackrabbits, especially in Arizona, Colo- rado, and the Great Plains (Arnold 1942, Reigel 1942, Lechleitner 1958, Sparks 1968, Hans-en and Flinders 1969, Flinders and Hansen 1972, Uresk 1978, Fagerstone et al. 1980, Johnson and Anderson 1984). These studies show that jack- rabbits are opportunistic feeders, varying their diets depending on available forage. In .spite of the relatively large number of pnblications reporting the feeding habits of black-tailed jackrabbits, few have been con- ducted in New Mexico and the Soutliwest. Dabo et al. (1982) found jackrabbit diets were composed of many species, but only a few spe- cies of grasses and forbs form(>d die bulk of die diet. They found Uiat diets, inlerred from fecal analysis, differed among habitats for jackrabbits during Slimmer and fall. In c()ntra,st, Fatchi et al. (1988) found similar diets amoue habitats on similar raugeland. The present stud\' represents a continuation of earlier studies and should add to understanding seasonal and \earl\ fluctua- tions in diets of black-tailed jackrabbits. Study Area The study was conducted on the New Mexico State Universitv College Ranch about 40 km north of Las Ciiices, New Mexico. The ranch lies on the Joniada Plain between the San Andres Mountains and the Rio Grande at an elevation of about 1300 m (Wood 1969, Valen- tine 1970). The climate of the Jornada Plain is semiarid, with a vearh' mean temperature of about 16 C. Mean monthly temperatures are highest in June (35°) and lowest in Januan- ( 13°). Average annual precipitation is 32 cm (range 9.2-36.2 cm), of which about 509f falls during Jiil\-, August, and September (Paulsen and Ares 1962). Fecal pellets from black-tailed jackrabbits were collected from six vegetation t\pes (habi- tats): (1) mesquite (Prosopis glandulosa) grass, (2) snakeweed (Guticnvzia sarothrac), (3) mixed shrub-grass, (4) black grama, (5) creosotebush [Larrca tridoitata), and (6) tar- bush [Flourciisia ccnuia). These \egetation t\'pes are characteristic of destMt grassland and jDepiutiiK'ntof Aiiimal;ui(l K^uii^c .Sdciiccs, New \U-x\m Slate rniwiNih, UusCnurs. New McMcdSNllKv I'lvviil a^lllr(■s^: Sec-tor tor Ij ■Departim-nl of Animal and Kaimc ScieiK-cs. New Mcxic-o Stale I'liiversitv, Las Cnices. \e\\ Mevieo SMK).! J Author to wliiiMicorrisponilente should l)eati(ln'S.sc(L Dcparlim-nt <>l' Kxpcrimcntal Statistics, New .Mexico State Uni\ersit\ . Las Cniccs, New .\h\ieo SSOI):; [■stock, Me/aiii.(iiiiiei 300 19921 Bl.U.KTAlLKD |A(;K1UBB1 r DlKTS 301 desert shnihlaiuls (Huinjilin'x 1958). Major grass species include black ij;iaiiia {Boiiteloitd criopodd), mesa dropseed (Sporohohis ficxuosus), tliiffgrass {Ehoiicuro)i piilchelltini), and threeawais {Aristida spp.). Abundant torbs include leatlienveed croton {Crotoii pottsii), \\()()I\ paperllower {PsilostropJw l(i^cti)uie), siKerleaf nightshade {Solanmii elaeagiiifoliiim), and other species. Shnibs inchide mesfjuite, creosotebush, and tarbusii. Methods )ackrabbit lecal material was collected innn each \egetational tvpe in June, August, and October' 19SS. The sample consisted of 15-20 pellets collected randomh' on each date and in each ol t\vo replications of each vegetational tvpe. Fresh pellets were identified b\' their shim appearance. Field obsenations indicated that pellets lost their shim appearance within a week of deposition. The pellets were dried and ground to pass through a 1.0-mm screen in a Wiley mill. The gromid material was prepared as described bv Bear and Hansen (1966) and Holechek (1982). Five microscopic slides were prepared from each sample, and 20 random fields were read from each slide (Holechek and Wura 1981 ). Individual plant species were iden- tified by comparison with known reference slides. All identifications were made bv the senior author with an accuracy of 94%. Calcula- tions of percent composition bv weight were made following procedures outlined b\- I lolechek and Gross ( 1982 ). Microhistological examination of fecal mate- rial has some limitations in diet evaluations (Holechek et al. 1982). Problems are related to differential digestion of different species (Sidahmed et al. 1981), differential detection and recognition under a microscope (Westobv et al. 1976), and differential particle siz(^ reduc- tion (Crocker 1959). In spite of thest' limita- tions, fecal anaKsis is one of the main methods for quantifying diet composition of w ide-rang- ing herbivores. Statisticiil anal\ses of dietan' data were based on species counts using a .split-plot, com- pleteK' randomized design with \egctational type as the whole plot and sampling date as the split-plot. Differences among tyjDes, periods, and the interaction were analvzed using a categorical modeling procedure (Proc Catmod, SAS Insti- tute 1985). Proc Catmod is a program for ana- 1\ zing relati\e frequenc)- data by chi-,s(|uare tests. I lerbage standing crop (an estimate of herb- age availabilit}') was det(>rmined by clipping herbaceous species from ten 0.5 x 1.0-m (juad- rats, located randomlv in each of the two repli- cations within each xegetational tvpe, at the time the fecal material was collected. Herbage was separated bv species, oven-dried (70 C), and weighed. Shrub biomass was determined for the major species bv dimension analvsis as described bv Ludvvig et al. (1975). Preference indices were calculated as the ratio between the amount each species contributed to the diet div ided bv the composition in the standing crop (Kiaieger 1972). Onlv tho.se prefenMice indices greater than 2 are reported in this papei- to indicate those species with a relativt'lv high degree of preference. Results Herbage Availabilitv Grasses contributed more tlian liallOf the herbaceous standing crop onlv on the black grama tvpe (Fig. 1). GeneralK grass composi- tion increased from June to .August, except on the creosotebush t>pe. Summer is th(> major growth period for the C4 perenniiil grass species in this area (Pieper and Herbel 1982). Forbs contributed more than 50% to the plant stand- ing crop on the mes(|uite-grass, black grama, and snakeweed t)pes (Fig. 1). Shrubs were abundant (contributing about 2()9f of tlu> stand- ing crop) on the creosotebush, taibush, and mixed shrub-grass tvpes. Diet Composition Seasonal changes in jackrabbit diets appeared to be greater than standing crop a\ ail- al)ilit\ for grasses, forbs, and shrubs (Fig. 2, Table 1). Generallv, grass co)it(Mit of the diet peaked in August and declined until October (Fig. 2). Fori) content of the diet changed little sea.sonallv for jiellets collected on the tari)ush. creosotebush, and snakeweed tvpes. Forbs comprised a larger percentage of the diet in |une and October than in .August on the mes- (juite-grass and black grama tvpes. Shrubs gen- erallv contributed less than 25% of the diet, except for pellets collected from shrubby tvpes at certain dates (e.g., October on the mesquite- grass tvpe, October on the snakeweed t)pe. 302 Great Basin Naturalist [Volume 52 Creosotebush Snakeweed Type August October Tarbush Type Mixed Shrub-Grass Type August October August October Mesquite-Grass Type Black Grama Type August October June June Fio;. 1. Staiuliiiucropori^rasscs. lorl.s. and slinilvs on ditTeivnt \vs was rclatixcK Dropseed content of pellets collected from the small (e.g., mi.\ed shnih t\pe; Tahle 1 ). Th(\se creosotebush t\pe was consistent from June inconsistencies contributed to the significant through October (Table 1). vegetational t\pe x date int(>raction (P < .01; Black grama content of pellets was not dif- Table 2). ferent (F > .10) among \egetational t\pes, but 13ietar\ content of Ihiffgrass and threeawn was different among dates (P < .10; Table 2). In grasses was generalK' low (Table 1 ). I hmcx er, most cases black grama content of the diet Ihiffgrass contributed more than 227f of the diet peaked in August, but for some vegetational in [une on the black grama t\pe and more than 304 Cheat Basin Naturalist [Volume 52 a: lo C35 Ml-— j: oi CO oi o oi o lo 05 lO l- lr^ ci — ci ci t- CC Ol t- c-l o c:r> — ■ CO QC I- oi c£: c: lO cc -t c cc ;c; 1^ — CO oi Lo lO — I- I- lO -t X lO- 1- ^ oi -r m — CO O ol I- ci ;/r X CC LO a: O X O O 32 cjo — ' m ;c :;5 I- a> O — X - m CO lO X Sc ai 1-' — x i- Ol -r < '^ iq •rr Ol l-^ cc CC f>i 05 ,:L (M CO o oi x X o; lo — -r o c: LC uo — X X oi -r O cc; C CO" — X -to o in C: — ' -t X CO — X -T — I - LO CO ;:; ic lo x — C: O c-i O v^' O CO lO 0> — CO lO — — no lO — LO no lO -t OI X- LO -t lO -t X X c: oi cr: LO — CO O] — -1- — X OI -f C: X O LO oi t- X — o oi CO CO lO CC I- 1 - — lO OI X X C: oi C OI XI- LD O UO 3; O] CO lO -^ oi c: CO X CO 35 X X — ■ oi — ■ 35 o] x; p oi ' — ■' CO I- CO o 1- — ■' no I- -r o X ;c i-^ Ol LO X 10 — X ;C X 35 x oi — ■■r - ^r '.■•' i 5 r ■■r. _^ ■31- ?; tr •£ t --> rr^ t H •i; e J H u. x""?^""";/? x"x-ii J: 1992] Black-tmu'I) 1 ACKiuHHiT Diets 305 cc o] ac 02 05 l- CO f>i 3C ^ X c-\ tT CO «D 00 oi lo -* CO in t-^ g cj m cc oi in t^ ■* I- — oc in f>i 00 in oi o CO ^ CM t- -H — Ol — ;r c^ — & ;^ m r^ X o\ h} t- in — ' X c^ ^ X t- CC 35 m C: ^ ^ CC CC 1-; O in o in c O CO in o in in in in 35 CO CO o> O t- o o 05 c-i ai z z z -H 05 OS — cc in in -C: Irass Snakeweed Creosotebush Tarbush Dropseed Black grama June June, Aug., Oct. June Aug. Oct. Oct. Fluffgrass June. Oct. Oct. June June June Abert's hnckwheat Oct. |une, Aug., Oct. Aug. Snakeweed June Desert hailexa Oct. Dcvsert hollv Aug. June. Oct. Aug., Oct. Oct. Dwari dalea Oct. Fendler's hladdei'iiod Aug.. Oct. [inie June Gloheniallow Aug.. Oct. Aug. June, Oct. June, Aug. Ihinenopappns |une Leathenvced c rot on June, Aug. Aug., Oct. June, Aug. June, Aug. June Rattlesnake wet 'd June Oct. SiKerleaf nightshade June, Aug. Aug. [une, Aug., Oct. June, Aug. Speetacle]:)od Oct. Oct. WooK ])aperno\\'er Oct. June, Oct. June June Mcsqnite June Aug. Yucca June, Aug. 12% in June and August on the mixed shrub t\pe, and in June on the snakeweed t\rpe (Table 1). Threeavvns C()ntri]:)nted l(\ss than 9% of the diet on all dates and vegetational tvpes. Other grass speeies made small contribu- tions to the diet. Plains bristlegrass {Setarid l('UCO])il(i), vine mesfjuite {Paniaiui (^hliisin)i). and burrograss (Sclen)])0(^on hrevijoliiis) did not differ in diets {P > .10) among vegetational t\pes or dates, and the vegetational type x date interaction was not significant (Table 2). Forb content of jackrabbit diets varied over time and vegetation t\])e. For example, the con- tent ol leatlienveed eroton differed significantK (P < .01 ) among vegetation tvpes and dates, and the vegetational type x date interaction also was significant (P < .01; Table 2). Its content \arietl from about 24% in pellets collect(>d dnring Augu.st in the tarbush tyj^e to none in the mixed shrub txpe at the same tinK\ LeatJKMAveed eroton appeared to be an important component of the diet on the black grama, mesquite-grass, and snakeweed tvpes during most seasons (Table 1). Dietarv content of other forbs was inconsistent among \ egetational t\pes and dates (Table 1). Russian thistle {Salsola ihcrica) was the onK forb species with a nonsignificant (P > .10) \egetational t\pe x date interaction (Table 2). Shrub content of the jackrabbit diets was also inconsistent among vegetational tvpes and dates. Mescjnite contributed substantially to the diets on most vegetational txpes between June and October. Mescjuite constituted more than 24% of the diets on the snakeweed t\pe in October, bnt onI\ 1% on the creosotebush t\pe in August (Table 1 ). Yucca {Yucca t'/^/fr?) contrib- uted more than 7% of the diet from the creosotebush t\pe in June, but was not found in j)ellets collected from the snakeweed t\pe on any date (Table 1). However, several shrubby species did not show a significant (F > .10) vegetational t\pe x date interaction (cnicifi.xion 19921 Black TAUJ::!) jACKiivBiiir Die rs 30' thoni [Kochcrlinia spindsa]. creosotcbiish. zin- nia [Zinnia (icco.sa]. and ephetlra [Ephedra spp. ]). Dit'tan- Preference The preference index was generalK helow 2 for most grass species (Table 3). However, jack- labbits apparentK' preferred black grama on all dates in the mesquite-grass tyjje. Flnffgrass was preferred dining some months on all t)pes, except for tlie mixed shrub-grass txpe. The preference index exceeded 2 for flnffgrass in June on four of the vegetational t\pes. The preference index exceeded 2 for se\'eral forb species (Table 3). Those with a preference index exceeding 2 for more than six combina- tions of \egetational t\pe and dates included desert hollv {Perezia nana), fendler bladdeipod [Lcsquerella femUeri), gloliemallow {Sphaer- alcea spp.), leathen\eed croton, and siherleaf nightshade. I3warf dalea [Dalea nana) was pre- ferred onlv in October in the black grama tvpe. Dabo et al. (1982) found dalea was highlv pre- ferred and comprised as much as 65% of the diets in the fall on grassland vegetational t\pes. Mes(juite and \ucca showed a preference index abo\ t' 2 for June and August on three \egeta- tional txpes (Table 3). Discussion I3lack-tailed jackrabbits in southern New Mexico appear to i^e opportunistic feeders. Although this stud\' and earlier ones indicate that as man\- as 30 plant species can be found in fecal samples at an\' one time. 5 or 6 species generalK' made up the l)ulk of the diet. Forbs often contribute a greater proportion of the diet than grasses, but the important forb species \ ar\ considerablx among locations, seasons, and \ears. Leathenxeed croton is perhaps tlu^ main- sta\' of the diet auKjng the forbs, although se\- eral others, such as silverleaf nightshade and wooK' paperflower {Psilostrophc ta<^ctinae), contribute substantial amounts to the diets. Dropseed, black grama, and tlulfgrass appear to he the major grass species. (,'ontrar\ to cattle, which utilize black grama niaiiiK during the dormant season ( I^osiere et al. 1975. l^odriguez et al. 1978), jackrabbits appai"eiill\ consume more black grama during the sunnner growing season. Consecjuentlw high jackrabbit densities could reduce the amount of black grama a\ailable for cattle later in the \ear. Mesquite appears to be the main shiiibb) sp(^ci(^s in the diets, although preference for mes(juite was not high. Othei- important shiaibs xaried c()nsiderai)l\ o\ci- time and space. AcKXow i,Ki)(;\ii'.\is This is [ournal Article No. 15f")() of the New Mexico Agricultural E.xperimenl .Station, l.as Cruces. LlTER.\TUHF, C:iTi;i) .Aj^NOLD, |. V. 1942. I'^oraiieconsuiiiption aiRlprclciciiccol experiiiRMitulK ii'd .-Xrizoiia aiul antelope jackiahhit.s. Uni\ersit\()i .Arizona .Agriciiltnral Experiment Station Bulletin 98. SB pp. Be.AR. G. D.. .\ND H. M IIwsf.N 1966. Food haliits. growth and reprodiietion ol white tailed jaekrahhit.s in .southern Colorado. Colorado State Uni\ersit\ .Agrieul- tiu-al E.xperinient Station Technical Bulletin 90. .59 pp. Ciux.KER. B. H. 1959. Coasnniption of forage by hlack- tailed jackrahhit.s on .salt-de.sert ranges oi New Mexico. Journal of Wildlife Management 30: .3()4-.'31 1. D.\BO, S. M., R. D. PiEPER, R. F. Beck, and G. M. Soltii- WARD 1982. Summer and fall diets of black-t;iiled jackrabbits on semidesert rangeland. New Mexico State University Agricultural Experiuienl Station Research Report 476. Fa(;erstone. K. A., G. K. L.\\()iE, and K. E. Grifkitii, Jr 1980. Black-tailed jackrabbit diet and densitx- on rangeland near agricultural crops. |ournal ol Range Management 33: 229-232. F.-MEHl. .M.. R. D. PlEPER. AND R. F. Beck. 1988. SciLsonal food habits of black-tailed jackrabbits (Lcpus ctilifonii- C!/.v) in southern New .Mexico. SouthwestiTU Naturalist 33: 367-370. Flinders, f. T, and R. M. Hansen. 1972. Diets and hab- itats of jackrabbits in northeastern Colorado, (.'olorado State University, Range Science Department. .Science Series No. 12. Fort Collins, Colorado. 29 pp. Hansen R. M.. and |. T. Flinders. 1969. Food habits of North .\iiierican hares. Colorado State Uni\ersit\'. Range Sci(^nce De])artnient. Science Series No. I. F'ort (."ollins, (."olorado. 18 pp. I lolECllECK, |. L. 19S2. Sample preparation technitjues for microhistological analysis. Jounuil ol Range Manage- ment 35: 267-268. IIoi.ECHEK, J. L., AND B. D. Gross 1982. Evaluation of different calculation procedures for microhistological analysis. Journal of Range .Management 35: 721-723. IIoi.ECHEK, J. L.. ;lnd .M. \a\ R\ 1981. The eiVect of slide and irecjuencx of obsen ation numbers on the precision of microhistological aniilvsis. Journal oi Range Man- agement 34: .337-338. IIoi.ECHEK, J. L.. M. V.u ra, and R. D. Pieper 1982. Botanicid composition determination of range herbi- vore diets: a review. Journal ol Range Management 35: .309-315. iliMiMIREV. R. R. 19.58. The desert grassland. Botanical Review 24: 1-64. Johnson. R. D., and J. E. .Anderson 19S4. Diets of black-tailed jackrabbits in relation to population den- sit\- and \-egetation. Journal of Rimge Miuiagement .37: 79. Kkiecer W. C. 1972. Exaluating animal forage prefer- ence. Journal of Range Management 25: 471-475. 308 Great Basin Naturalist [Volume 52 Leciileitmch. R. R. 1958. Certain aspects of behavior of the black-tailed jackrabbits. Aniericaii Midland Natn- ralisteO: 145-155. LiiDwic;. J. A., J. F. Reynolds, and P. D. W'iiitson 1975. Size biomass relatioii.ship.s of several (^liihualiuan desert shnibs. American Midhuid Natnralist 94: 451—461. Mc:AdO(). J. K., .\ND J. A. YoUNc; 19S(). Jackrabbits. Rangelands 2: 135-138. P.\ULSEN. H. A., Jk . AND F. N. Ares. 1962. Grazing values and management of black grama and tobosa grasslands and associated shrub ranges of the Southwest. U.S. Department ol Agriculture, Forest Service Technical Bulletin 1270.56 pp. PiEi'EH, R. D.,AND C. H. Herbei 1982. Herbage dynam- ics and primarv producti\it\- of desert grassland ecosys- tems. New Mexico State University Agricultural Experiment Station Bulletin 695. 43 pp. Reigel, a. 1942. Some obsenations of footl locations of rabbits in western Kansas during periods of stress. Transactions of the Kansas Academy of Science 45: 369-375. RoDRi(;uEZ, J. G., R. D. Pieper, and G. S. Smith 1978. Botanical composition of cattle diets on desert grass- land range. New Mexico State University Agricultural Experiment Station Research Report 363. 4 pp. RosiERE, R. E., R. F. Beck, and J. D. Wallace. 1975. Cattle diets on semidesert grassland: botanical compo- sition. Journal of Range Management 28: 89-93. SAS. 1985. SAS users guide. SAS Institute, Inc., Caiy, North Carolina. SiDAHMED. A. E., S. C. Denham, J. G. Morris, L. J. KooNG, and S. R. R^dosevich, 1981. Precision of microhistologic;il estimates of goats from fecal analvsis and cell wall passage through the gastrointestinal tract. Proceedings of the Western Section of the American Society of Animal Science 32: 201-204. Sparks. D'. R. 1968. Diet of black-tailed jackrabbits on sancUiill rangeland in Colorado. Journal of Range Man- agement 21: 203-208. Uresk. D. W. 1978. Diets of black-tailed hare in steppe vegetation. Journal of Range Management 30: 439- 442. Valentine, K. A. 1970. Influence of grazing intensity^ on improvement of deteriorated black grama range. New Mexico State Universih' Agricultural Experiment Sta- tion Bulletin 553. Westobv, M., G. R. Rost, and J. A. Weis 1976. Problems with estimating herbivore diets by microscopic;illv identifying plant fragments from stomachs. Journal of Mammalogy 57: 167-172. Wood, J. E. 1969. Rodent populations and their impact on rangelands. New Mexico State Universitv Agricultural Experiment Station Bulletin 555. Received 9 April 1991 Accepted ISJulij 1992 Crcat Basin Naliirdist. 52(4), pp. 3()^)-ol2 SPECIES OF EIMERIA FROM THE TIIIRTEEN-LINED GROl \D SQUIRREL. SPERMOrHlLlS TIUDECEMLIXEATUS, FROM W YOMIXC; Rohcrt S. Scxillc ". l^ianc M. Tlionias , Hiisscll Pickcriiiij; . and \aiic\ 1.. Stanton Ans'iHACT. — Fi\e spt'tirs ol tlic coccidiaii iiciius I'.iiurvid (/■,'. hceclicyi [prevalence = 17.9%], E. cdllospcniiopliili- iiioraiiicD.sis [28.6% ], E. lariincrcnsis [ 16. 1% ]. and E. hilainclldla [3.6%] ) were reco\erecl from 56, 13-lined ground squirrels (SpcrDiopIjihis tridicemlimtaUis) collected from t\\() sites in eastern Wyoming. Two s(|uirr<^Is from one site were also passing an unidentified poKsporocvstic coccidian. Infected scjuirrels were found to harbor from one to three species simuItaneousK'. J'rtviousK these sanie eimerian species were found infecting sympatric populations of Wxoming ground squirrels (Spi'r- m<>j)liiliis clc'^diis) and \\ hite-tailed prairie dogs (Ci/rioiui/s Iciininis) at one nl the sites; it is suggested that the exchange of these generalist parasite species among co-occurring sciurid hosts contrihiites to the consistent prex'alence lex'els reported ill NWoiiiinti ground squirrels. Kci/ uonl.s: Eimeria. Spermophilus tridecemlineatus, prevalence, peihjsporoctjstic eoceidia. Shults ct al. (1990) reported the occurrence of six .species of eimerian parasites (Protozoa: Apiconiplexa) in sympatric populations of Wyo- ming ground squirrels (Spennopliilii.s eh''ears. Toft (1986) recognized Iano classes of para- sites: micro- and macroparasites. Macropara- sites (e.g., helminths) tend to produce long-lasting infections and are endemic in host populations, while microparasites (protozoa, hacteria, \inises) prochice short-lixed inf(^ctions and long-lasting inununits', resulting in oscilla- tions of infection frequence" (epidemics) within the host population. The stabilit\' for intestinal piotozoans reported 1)\' Stanton et al. (1992) does not support Toft's prediction regarding microparasites. While then" ha\e been no mechanisms propo.sed for maintaining stabilit\ in microparasite communities. Stock and Holmes (1987) proposed that species richness of intestinal lielmintli connnunities of grebes was enhanced b)' reduced host specificit\ which allowed parasite exchange among related hosts. One important factor in maintaining the stabil- it\" of eimerian assemblages is exchange of par- asite species among closel\- related sxnipatric host species. The puipose ol (his stud\ was to determine" which eimerian species are present in wild pop- ulations of 13-lined ground s([uirrels (Sjut- niopltihis tridecemlineatus Mitchill, 1821) and to assess the role these hosts pla\' in mainte- nance of the stable eimerian guild obsened in W\()ming ground s(|uirrels. MKTIIOD.S In 1991 we sampled 13-lined ground scjuir- nds from two locations: (1 ) a natixe short-grass prairie/ha\field 10 km south of Laramie. W\-o- ming (4LI2'\, 105°33'W). and (2) a native short-grass prairie/ha\ field 18 km .south of (-il- lette, Wyoming (44°r7'N. 1()5°31'W). At the Laramie site scjuirrels wvyc li\e- trapped using National lixe-traps once a month from |uK to September. 0\er the four-da\ trap- ping period scjuirrels were trajijoed using three 60 X 42-m tra{)ping grids with traj)s .set e\en- 6 m (162 total traj)s). Trai)s were set at 2000 hr and checked each morning by 0800 hr. .\t the (wllette site, six 4()()-m transc^cts and , Department of Zoolog)^ and Ph\ .siology , Box .3166, University ofWyoming, Uiramie, Wyominj; USA 8207r "Present address: Ontario Ministn' of Natural Resources. Wildlife Branch. Box 5000. Maple. Ontario L6A IS9, C:anada 309 310 Great Basin Naturalist [\ olunie 52 Table 1. Total percent infected and pie\alences (hosts infected vvdth given species/liosts examined) of eimerian species in gronnd-dvvelling scinrid hosts at Laramie and Gillette collection sites in Wyoming (% inf = total percent infected with FAmcrio: Elbe = £. hcccluyi; Eibi = K hihiuuihild: iMca-mo = E. rallospcnnaphili-inorainciisi.s: Eila = E. hihincrciisis: and Eisp = E. spermophili). Sciurid host %inf Eibe Eibi Eica-mo Eila Eisp Spennophilns tridcccinlineatiis Laramie (n = 41) 43.9 7.3 2.4 9.6 14.6 0 Gillette {ii = 15) 86.7 46.7 6.7 80.0 20.0 0 Total (n = 56) 51.8 17.9 3.6 28.6 16.1 0 S. cli-ffnts'^ Laramie (/; = 1007) 68.0 34.0 11.0 43.0 17.0 5.0 Ctpiomy.s Icncurus ' Laramie (n = IS) 94.0 83.0 17.0 22.0 0 0 'Prrceiitagcs for S. clcfiam ami C. Iciin ''From Shults et al. 1990. (U'tcTiTiineil li\ takine; liigliest of two sallies for E ivIlnspcnnDpliili or E f ^ Fig. 1. Photomicrograph of a polvsporocvstic coccidiim collected from a 13-lined ground scjuirrel ( 1250X Nomarsky interference) showing t\pical sporoc\st with residuum clearK xisiblc. six 50-111 transects in \arions vegetation t\pes were trapped dnriiig the second week in August (3870 trap-nights). Stations were 15 m apait, eacli consisting oi'one \ 'ic-tor rat trap, two Victor mouse traps, and one Sliernian H\e-trap. Sher- man traps remained closed during daxHght hours, and traps were c-hecked and reset at dawn and (hisk. All fecal samples collected from animals at both sites were placed in 2% potassium dicliro- mate solution at room temperature (25 C) for at least three weeks to allow oocyst sporulation for species identification. Ooc\sts were isolated 1)\ flotation in saturated sucrose solution (specific gra\it)' = 1.2) and identified at lOOX objective with an Olvmpus (CH) microscope. Identifica- tion to species in most cases could be accom- plished based on oocyst size and external and internal moiphologv. Howexer, for Eimeria callo- spennophili Henn; 1932 and E. inorainencsis Torbett et al. 1982, the respective size ranges overlap making identification dependent on internal moipholog)'. Unfortunately, rarely do all oocvsts in a fecal sample sponilate. Therefore, although both species were identified, the two are combined into a single species complex, E. callospcnnopluli-inorainoisis. Comparisons of total percent infected and prevalences of each species between the two sites were made using chi-square tests (Number Cruncher Statistical System \ersion 5.03; Hintze 1990). Results ForK'-one 13-liiied groiuid scjuirrels were sampled at the Laramie site and 15 at the Gil- lette site. Five species of Eimeria were found infecting scjuirrels in both populations. Overall, 51.8% of all squirrels examined were infected with at least one species of Eimeria. The total percent infected was significantK higher at the (Gillette (86.7%) than at the Laramie site (43.9%; P < .05). Infected squirrels at Gillette also had higher parasite species richness (1.77 species/infected squirrel) than at Laramie (1.17). Total percent infected and pre\'alences by species at each site are presented in Table 1. Overall, the Eimeria eallospermophiU- moraineiisis complex was the most prexalent species found, infecting 28.6% of the 56 hosts examined. SisnificantK' more hosts were 19921 EiMEiUA FKUM 13-Lim-:d Groum) Sgi iukkls 311 infected with this species complex at the CTillette than the Laramie site (8()9f \s. 9.67r ; P < .05). Ehiwrid bccchciji HemA; 1932 was tlie second most pre\alent species fonncl. inlectintj; 1 7.9% ot the hosts examined. SignificantK' more hosts were infected at the Gillette site (46.7% vs. 7.3%; F<. 05). Eimeria larinwrcnsis N'etterling, 1964 was fonnd infecting 16.1% of the scjuirrels exam- ined. Prexaleiice was higher at the Gillette site (20% \s. 14.6%), but the difference was not significant (P<. 05). Eiinerio bilamellata was the least common species found dming the stnd\' (3.6%). Again, prevalence was higher at the Gillette site (6.7% \s. 2.4%), but the difference was not significant (F<.05). Two squirrels at the Laramie site were also infected with a subspherical poKsporocwstic coccidian (Fig. 1) with 10-12 sporoc\sts. The number ot sporozoites could not be determined due to the large amount of residuum present in the sporocvsts. Mean size for 15 measured oocNsts was 38.62 x 30.20 |jl. Sporocvsts w^ere spherical and measured 10.65 x 10.65 |jl (/j = 15) and had no steida bod\'. Both oocvsts and sporocwsts contained numerous residual bodies. Attempts to infect t\v() captix e WVoming ground S(juirrels {SpcrDtophilus dedans) were unsuc- cessful. DISCUS.SION The occurrence of E. beccJiet/i, E. hihi- iiwllata, and E. morainciisis in 13-lined ground scjuirrels constitutes new host records for these species in this host. Polysporocystic oocysts have not been pre\iouslv reported from sciurid rodents. Levine et al. ( 1955) identified two poK- sporocystic species, Klossia perf)Iexens fiom deer mice (Peromysais maniadatiis) and K. variabilis from the western big eared bat iConjiiorliiiuis rafinesc/iiii) collected at the Grand CauNon, Arizona. Becau.se all species of Klossia previousK' described were found in inxertebrates, Levine et al. (1955) postulated tliat the t^vo species were parasites of in\erte- brates eaten b\- the deer mouse and bat. Dornev (1965) reported finding tvvo poKsporocwstic oocysts in feces from a woodchuck (Mannota inonax) from Pennsylvania that resembled the descriptions of the two species in the genus Klossia reported b\ Le\ ine et al. ( 1955). Donie\' speculated that the two oocysts might represent spurious infections of in\ (Mtebrate origin. Based on thes(^ reports, it is likcK that the poK- sj)()roc\stic coccidian ol)ser\-ecl in 13-lined scjuirrels is a member of the genus Klossia and possibly of invertebrate origin. Howexer. iden- tification to species recjuires further woik. including the identification of the priman host. The results of this study indicatc_' that while the eimerian fauna of 13-lined ground scjuirrels is \eiy similar to that of \V\oming ground scjuir- rels and white-tailed prairie dogs, at the Lara- mie site there were some differences in the prevalences of the different parasites. Of the fi\e species found infecting 13-lined scjuirrels. all ha\e been reported previousK from svmj)at- ric ground squirrels (Shults et al. 1990, Stanton et al. 1992), and all have been reported from w liite-tailed prairie dogs in WVoming (Todd and Hammond 1968a, 1968b, Todd et al. 1968, Shults et al. 1990). However, at the Laramie site 13-lined scjuirrels were not as frecjuentlv infected and had lower prevalences than Wvo- ming ground squirrels for all species and lower prevalences than white-tailed j)rairie dogs for E. beeclieyi, E. callospcrniopliili-inorainciisis, and E. bilamellata. Values for 13-lined squirrels at the Gillette site (where no other species of sciinids were present) were more similar to those forWvoming grovmd scjuirrels at the Lar- amie site (Table 1). Additionallv. W'voming ground squirrels had greater species richness than 13-lined squirrels (Stanton et al. 1992). Species richness for prairie dogs has not been reported. Results indicate that related sv nipatric hosts can be infected by the same species of Eimeria, which mav contribute to the stabilitA of the eimerian guild. ACKNOW Li:i)(;.\lENTS This resc^arcli was suj)j)c)rted in part bv the Dej)artnient of Zoologv and Phvsiologv and the Office of Research, Universit\ of W'voming, and NSF Grant #BSR-8909887. ' LiTKHATlHK GlTED DoKM V H. S. 1965. Eimeria tuscarorensis n. sp. (Protozoa: EiiiK-iiiilae) and rede.scriptions of other c-occidia of the w(K)dchuck, Marmota monax. Journal of Protozoologv' 12: 42.3-426. I.I \ INE, N. D., V. I\'KNs. .WD F.J. Kkuidkmkh 1955. Two new species of Klossia (Spirozoa: Adeleidae) from a deer mouse and a hat. Journal of Parasitology- 41: 623-629. 312 Great Basin Naturalist [Volume 52 SiiULTS. L. M., R. S. Skvillk. N. L. Stanton, and G. E. Mf.nckf.ns. Jr 1990. Einwria sp. (Apicomple.va: Eiineriidae) from Wyoming ground .s(juirrel.s {Spcr- tnophilus clegam) and white-tailed prairii> dogs {Cijn- oinijsleiiciint.s) inWVoniing. Great Basin Naturalist5(): 327-331. Stanton. N. L.. L. M. SiiiiLTs, M. R\hkek. and R. S. Sf.\ti,lk 1992. Coccidian assemblages in the Wyo- mingground squirrel, S})enn()])liiliis elc'^diis. Journal of Par;Lsitol()_g\- 78:323-,328. Stock, T. M., and J. C. Holmks, 1988. Functional rela- tionships ;uid microhabitat distributions of enteric hel- minths of grebes (Podicipedidae): the exidence for interactive communities, journal of Parasitologx 74: 214-227. Todd. K. S., Jr.. and D. M. Hammond 1968a. Life cycle and host specificity- oiEiiueiia callospennoph'di Heniy, 1932 from the Uinta ground squirrel, SjU'niiopliilns annatiis. Joimial of Protozoology- 15: 1-.8. . 1968b. Life cycle and host specificiK- of Ehueria lariiiwrcnsi.s Vetterling, 1964 from the Uinta ground squirrel, Spennophilu.s (iiiiuiiiis. fournal of Protozool- o,g\- 15: 26.8-275. Todd, K. S., Jk . D. M. Ha.mmond and L. C. .Anderson 1968. Observations of the life cvcle of Eiuwria hilanu'llafa. Henn- 1932 in the Llinta ground squirrel Speniutphiliis (innatus. (ourual of Protozoology' 15: 732-740. Toft, C. A. 1986. (xjuununities of species with parasitic life-styles. Pages 445—463 /» J. Diamond and T |. C^ase. eds.. Community- ecology-. Harper and Row. New York. Received 12 Fehnuin/ 1992 Aceeptecl IS Septeuiher 1992 (iivat Basin Xatiiralist 52(4). pp. 313-.320 PLANT AGE/SIZE DISTRIBUTIONS IN BLACK SAGEBRUSH {ARTEMISIA NOVA): EFFEGTS ON COMMUNITY STRUCTURE James A. Youiiy; and nei)ra E. Palmqiiist Abstiuct. — The demographv of black sagebrush (Ai-tciitisia nova Nelson) wius iTivestigated in the Buckskin Mountains ofwesteni Nexacla to determine patterns of stand renewal in sagebrush communities currentK' tree Ironi wildiires. Biouiass sampling was conducted to de\eIop growth ckisses that reflected apparent age of the shrubs. The densit\ of black sagi'l)nish plants was twice that of basin big sagebrush (A. tiidcntata ssp. trklcntata Nutt.) in adjacent comunmities on contrasting soils (2.2 \ersus 1.1 plants per m~). Black sagebmsh accumulated only 759^ as much woodv biomass as big sagebnish. f-legression equations were de\eloped and tested for predicting total wood\ biomass, current annual growth (CAG), and leaf weight of black sagebnish plants. Apparent age classes were de\elopetl both lor the black sagi'brush plants and die sub-canop\' mounds on which thev grew. Discriminant lUUiKsis was used to test this classification system. Plant succession, apparentk' controlled b\ nitrate content of the surface soil, appealed to eliminate the successful establishment of black sagebnish seedlings on the mounds. After the shnibs die, the mounds eventiuilK deflate. We projiose tliat mounds reform aroiuid shrub seedlings; but because seedling establishment is so rare in these coiiimunities. this could not be xcritied. Kci/ iiords: hioinass. shnth .succession, dcscii sail fonnnlidii. soil nil rale, black sY/gcAn/.v//. Artemisia nox a. Black .sagt'hru.sh [Aiicniisid uolci Xclson) is one of tlie dwarf sagebnish species which col- lectiveK' constitute about half the sagebitish \egetation in Ne\ada (Beetle 1960). Black sage- 1 irush plays a dominant role in a number of plant communities in the Great Basin (Zamora and Tueller 1973). Rarel\- does black sagebrush share dominance with another species of Artc- inisia. In the section Tridentate of the genus Aiicniisid. black sagebrush is perhaps the spe- cies most adapted to arid en\ironments. Black sagebnish is closeK' associated with shadscale [Atriphw conjciiijolid (Torr. & Frem.) Wats.] dominated landscapes (Blaisdell and Holmgren 19S4). The browse of black sagebnish is higliK prcdcrrcd b\' domestic sheep {Ovis aries). pronglioni {Antilocaiya anwiicana), and Sage Grouse {Centrocerens orophasianus) . From the 189()s until the late 195()s, black sagebni.sh plant communities in the Carson Desert of Ne\ada werea\ital part ol winter range for tlu^ domestic range sheep indnstn". Years of e\cessi\ e brows- ing b\' sheep actually shaped the outline of black sagebnish shrub canopies; Zamora and Tueller (1973) reported the\- had difficult\' in finding relic communities in high range condition. Vetretation of the Buckskin Mountains of west central \e\ada is characterized In black sagebruslVdesert needlegrass {Sfipa spcciosa Trin. & Rupr.) plant communities. The Buck- skin Mountains are located 100 km southeast of Reno, Nexada, in the rain shadow of both the Sierra Ne\ada and Pinenut Mountains. This is a portion of the Canson Desert in which Billings (1945) suggested that Afn/^/c.v-dominated salt desert shnib \egetation occurred because of atmospheric drought rather than occurreuc(" of soluble salts in the soil. Ifwe compare the black sagebrush comniunities of the ISuckskin Nh)un- tains with those describetl in the regional stutK conducted b\ Zamora and Tueller (197.3), we find that the highest-elexation, north-facing slope communities of the Buckskin Mountains correspond to the most arid communities pre- viouslv described. P'rom this we assume the black sagei)riish communities in this stiuK rep- resent an arid (extension of this t\pe. Only rec(^iitl\ haxc occasional wiUllires of any extent occurred in black .sagebrush commu- nities in western Nexada. The fires that ha\e occurred ha\e been associated with the recent si)read of the ali(Mi annual cheatgrass {Broinus tcctoiiim L.i into these arid emironments (Young and Tijiton 1990). ApparentK for much USDA, .Agricultural Ht-.si'arcli Senile. 920\'allc\ Kciad. Heuo. Ne\aila S9.512 313 314 Great Basin Naturalist [X'olume 52 of the tAventietli centun- these communities have not been subject to wildfires because of lack of herbaceous vegetation to cany the fire. Because of the lack of trees to produce fire scars, it is difficult to determine whether these sites were subject to periodic burning under pristine conditions. This is in sharp contrast to basin big sagebnish communities where periodic cata- strophic stand renewal by burning from wild- fires has been common. The lack of catastrophic stand renewal in black sagebrush communities should be reflected in the age/size class struc- ture of the communities. Our puipose was to determine the age/size distribution of black sagebrush plants to deter- mine community structure. Materials and Methods Studies were conducted from 1984 through 1988 in the Buckskin Mountains located about 100 km southeast of Reno, Nexada. The geo- logic features of this moimtain range have been described in detail bv Hudson and Oriel ( 1979). Vegetation and soils of the range ha\e been mapped and related to the geologic map of the area (Lugaski and Young 1988). The plant com- munities used in this study were located on the Guild Mine member of the Mickey Pass tuff This geologic unit consists of crvstal-rich, mod- erately to poorlv welded ash flow tuff (Proffett and Proffett 1976). It has been proposed that the soils (a) developed in place, (b) developed from subaeriallv deposited material from long- distance transportation, or (c) dexeloped from a combination of residual and subaerialh' depos- ited material (unpublished research, ARS- USDA). The bulk of the profile is an argillic horizon, about 50 cm thick, which consists of 50% or more clay-te.xtured material. It is pro- posed that this clay horizon is a reHc of a soil that de\'eloped on the site and whose original surface horizon lias been removed by erosion. The important point is that the clay horizon, which is interniittentl) exposed on the soil surface, developed under different environmental con- ditions from the current surfiice horizon. The current surfiice soil consists of a relatively recenth' deposited layer, apparently from sub- aerial deposition, that is largely confined to mini-mounds beneath the canopies of the black sagebrush plants. The soil is classified as a fine, iridic, montmorillonitic, Typic Paleargid. S})atial structure of the black sagebnish com- nuinities was detennined by .sampling five .stands located along the western flank of the Buckskin Mountains. The five stands, located on the same outcropping of Micke\' Pass tuff, were separated bv small canvons where the westerK^ tilted ash flows were broken bv faulting. All sites were west facing and located in a band alono; the mountainside at 1720-1780-ni elevation. A starting point was located on aerial photo- graphs in each stand, and 10 plots, each 10 m" in area, were located random Iv along Line tran- sects parallel to the slope. A total of 50 plots were established (5 stands X 10 plots per stand). In each plot the following were determined: (a) shnib densit)' by species, (b) crowii coxer of shnibs (ocular estimate), (c) shnib height, (d) area of mound and interspaces, and (e) herba- ceous cover (ocular estimate). Mound co\'er refers to the slightly raised areas beneath shrub canopies where subaerialh' deposited soil and saltation deposits accumulate. At each plot location the herbaceous \egeta- tion frequencv was sampled with 100 step points arranged in 4 lines of 25 points each following the procedures of Evans and Love (1957). The herbaceous xegetation was resampled annually. Using the same starting point, but bv placing the transects up and down the slope, 25 black sagebnish mounds were located in each stand. The shrubs rooted on each mound were mea- sured for (a) height, (b) ma.ximum and mini- mum crowni diameter, (c) stem number (as black sagebnish ages the cambium splits, forming multiple-stemmed plants), and (d) stem diame- ter at the soil surface (diameter of the group of split stems). The aerial portion of the plant was subdixided by clipping into the following cate- gories: (a) coanse stems, 2.5 cm or larger in diameter; (b) fine stems, 0.25 to 2.4 cm in diam- eter; (c) current annual growth; and (d) leaves. The material was dried at 80 degrees C for 24 hours and weighed. After the aerial portion of the shrub was remoxed, the litter beneath the canopx' xx^as col- lected and screened through a 2-mm screen. The material too coarse to pass through the screen xxas saxed, dried, andxxeighed. The max- imum and minimum diameters of the mound xvere measured, and the height of the mound xx'as determined bx' digging to the clax' horizon. The number of perennial grasses rooted on the mound xvas counted bv species, and the cover of cheatgrass xx^as estimated ocularlx' per mound. A series of age/size classes xvas established fcjr the black sagebrush plants sampled. These 1992] Black SACKiiiasii Dkmocivm'Iiv 315 Table 1. Mean plus standard error (SE) for shrub densitv- per m". percent ])rojeeted eanop\ cover, fre(juenc\- (lO-m" iloti within stands (.V = lOl, and constanc\- among sttinds (A' = 5). Species Densih^ SE Cover (%) SE Frequency (%) SE Constancv (%) SE Artemisia nova 2.2 0.40 22 2.4 100 0 100 0 Chn/sotliainniis riscidijloni.s 0.7 0.10 o 0.4 40 S SO 8 Ephnda iiciiitlcnsi.s 0.3 O.OS 1 0.4 64 10 100 0 Tc'tni(lt/mi(i ommimit\ ("ompetition The plant comnumities of the Buck.skin Mountains dominated bv black sagebnish are low ill diversitv (Table 1). Green rabbitbnish [Chnjsothaminis liscklijlonis (Hook.) Nutt.] occurs in patches in the community Nevada ephedra {Ephedra ncvadciisis Wats.) is rather evenly distributed through the black sagebnish communities, but at a low density Littleleaf horsebnish (Tctrachpiiia ") is a rel- ativeh infrequent component of the communi- ties. The two species of Eiioj)si.s liiiinciiuklcs - - 1 0.2 - - .\N\r\i.(;HASS Broiiiiis Icctoniin 44 6.6 14 2.8 76 3.8 PKHKNNI.\LF()Hli Cast i Ih'ja cliromo.sa 1 0.2 1 0.2 - - Spluicmlcai pairifolid - - 2 0.3 - - Phlox luHxIii - - 3 0.3 - - AWIALKOKB Enxliiiin cinitariinn 5 0.8 - - 2 0.8 Dcsairaiiiiti piitiiata - - - - 5 0.7 Sistjmhriiiin altissiitiiiin 5 0.9 - - 10 0.8 ■'Inclicatt's li's.s than 19r avcraiit- ol l)a.sin big sagebrush adjacent to the western edge of the Buckskin Mountains (Young et ah 1989). This allowed comparison of the produc- tion of bioniass of basin and l)lack sagebmsh from the same area. The basin big sagebrush communit)' had a .sandy loam surface soil and a greater soil depth (Haplargids deri\ed from meta- N'olcanic sources). Big sagebmsh ages were clumpt>d at 5.5-60, 40^5, and 10-15 years old. The general aspect of the t\vo communities is strikingK' different, with the maximum height of th(^ black .sagebrush being 60 cm and that of the big sagebmsh over 1 m. In contrast to the central wood\' stems of the big sagebmsh plants, black sagebrush plants appear multi-stemmed. Despite the difference in height, the two com- munities have .similar biomass because of the higher detisit) of plants in the black sagebrush connnunit). There is more coarse and fine woody material in the basin big sagebrush com- munit)' (Table 3). If we assume both populations are the same age (assumption is necessaiy becau.se actual age of black sagebmsh plants could not be esti- mated), the rate of woody biomass accumula- tion was 13.2 g/nr/year and 64.5 g/m"/vear for black and basin big sagebmsli, respectively. The wide difference between the two connnunities is apparently due to the higher woody biomass of more mature basin big sagebmsh plants. Woody bioniass of black sagebaish was best predicted b\' the ecjuation: Y = 9.87 + 1.21 " XI + 1.12 " X2 + 0.88 ° X3 where Y = total woody biomass (grams), XI = fine stems, X2 = coarse stems, and X3 = root crown. R~ - .96 for this determination. YearK' growth hicrement was predicted b\ the e( {nation: Y = 16.96 + 0.26 " XI + 0.16 ^ X2 - 0.73 °X3- 0.14 "X4 where Y = current growth, XI = fine stems, X2 = coarse stems, X3 = iilant lieidit, and X4 - root crown. R~ = .57 for this determination, despite the inclusion of a fourth \ariable. Our third ecjuation predicted leaf weight: Y = 23.53 + 0.29 " XI - 0.93 ° X2 + 0.2 " X3 - 0.35 ° X4 where Y = leaf weight, XI = coarse stems, X2 = height of plant, X3 - fine stems, and X4 = plant density. These four \arial)les in the eejuation accounted for 64% of the variability' in the data. 19921 Bi^u;iv S.u;kbiu;.sii Di;.\iuc;haimiv 31' 30 20 10- 0- ■10 -20- -4 A A A A A A A A ® ® ®® ® ®® ®s)®®8e6® ® ®®(S®S® ®® ® ® ® ®^ ®®s® ®®s® ®®® ® ® ® ® ® ® ® — I 1 r -1 0 1 Canonical Fnc. 2 Fig. 1. Plot of l)Iatk sagebrush group membership based on plant characteristic (liscrimiuaut ecjnationswliereO = \oung. ® = mature. ▲ = patriarch. ■ = senescent, and □ = dead. Age/Size Classes The selected variables for both plant and mound characteristics were important contrib- utors in distinguishing between age/size classes and were good indicators of group composition (Fig. 1). Ver\- few niisclassifications occurred 1)\ use of the resulting discriminant functions. The bulk of the black sagebrush stands was composed of mature plants 20-60 cm tall with canopies 20-50 cm in dianu^er (Table 4). This is a wide range in height and canop)' size, but tl le 1 1 uitu re age/size class was distinguished f r( )n i young plants b\ the presence of up to 10% dead material in the canop\- and the beginning of the separation of the stem into individual cambium bundles. The patriarch class was distinguished from the mature class b\- an increase in dead material in the canopv (to 307c) and complete separation of the stems. The separated stems fbnned U-shaped flutes with the open end of the U toward the former center of the stem. It was not possible to establish tlie maximum age of the class because the center of the stem was missinji. The indixidual .section had at least 40 growth rings. Senescent plants formed the next, appar- cntK older, age/size class. In this cUiss at least 50% of the canopv was dead. Older black sage- brush plants do not get taller, prol)abl\ because tl wv ha\e no central stem to support the canopy. The diameter of the crowns does increase. There is a marked increase in wood\- biomass between the patriarch and senescent classes. Seedlings and \oung plants constituted only 6% of the black sagebnish populations (Table 4), 318 Great Basin Naturalist [Volume 52 TaBLK 3. Mean density (stem.s/ni ,) plus staiiclard error (SE) and oxcn-iln hioniass (g/ni") oi Aiicinisid nma and A. tridentata subsp. tridentata. Data for A. tridentata suhsp. tridcntata from a previous study (Young et al. 1989). Biomass per ■-> m" Species Deni 5it\- Co; u"se Fine GAG Le; .ives Total m"" SE g SE g SE g SE g SE g SE Artemisia nova Artemisia tridentata subsp. tridentata 2.2 1.1 0.4 0.3 750 ,S50 90 KM) .520 970 fiO 110 ISO 170 4.5 40 1.30 130 40 50 15.50 240 2120 420 T\HLK 4. Artemisia luna crown and hioniass characteristics for indixidual age/size classes. Demographic breakdown of black sagebnish communities In growtli classes. Glasses are related to age tor younger plants, but once stems separate, ages are not based on luinud rings. Grown characteristics BiomiLss char acteristics Dead Goarse Fine Age/size Height Diametei ■ Densit\- bi •anchlets stems stems GAG Lea\e Stem Percentage Age class (cm) (cm) {%) (%) (g) (g) (g) (g) number of stand (vears) Seedling 5 5 30 0 0 15 5 10 1 >1 2-5 Young plant 10-20 .5-10 .50 0 2S 64 .30 40 1 5 5^30 Mature 20-fi() 10-.5() SO 10 140 120 SO 60 Multiple 60 30-50 Patriarch 20-60 20-S() 60 .30 ,560 420 140 100 Multiple 17 40+ Senescent 20-60 20-100 30 60 9S() 640 60 .30 Multiple 12 •p Dead 20-60 20-100 0 100 910 320 0 0 ,Multiple 5 p with seedling.s being very rare. The separation between seecUing and young plants was based on the occurrence of coarse, woody biomass in the latter class. Young plants had entire stems with no exidence of division of the cambium. Mound Tvpes Eacli black sagebnish age/size class had a corresponding t)pe of sub-canopy mound. The only seedling found in the entire study was located in an interspace between mounds. Obvi- ously, one seedling is not a xalid sample, but tlie lack of seedlings is a critical factor in the d\ nam- ics of the communities studied. The first detect- able mound occurred imder young plants. Only 5-10% of the sub-canopy area imder black sage- brush plants in the voimg plant age/size class was covered with litter (Table 5). The litter was coTnpo.sed of fragnu^nts of black sagebnish leaxes. In the mature plant age/size class the co\er of litter and the weight of litter increa.sed (Table 5). The mounds were easily distinguished by both height and surface soil color and te.xture. The surface of the mounds appeared darker in color, and the reddish tinge to the cla\' surface soils of the interspace was not apparent. If the surface of the mound was disturbed, the dark color was replaced bv a gra\ish shade. Mounds appear to reacli their maximum height with this growth stage of black sagebnish. Mounds of mature plants had perennial grasses associated with the sub-canopy area. The most frecjuent perennial grass was squirreltail. Litter accumulations increased witli the patriarch age/size class, but height oi the mound did not increase. ApparentK; trapping of sub- aerial deposition material and saltation particles must be related to gro\\'th stage of black sage- brush plants in terms of crowii architecture. SubaerialK' deposited particles are ob\iousl\' \'er\' unstable and subject to redeposition if the\' fall in the largelv bare interspace among shrub mounds (Young and E\ans 1986). If litter accu- mulation increases on patriarch mounds, wliy do the\ not trap these secondan' erosion prod- ucts and the mound keep growing in height? Canopv stnicture changes with the patriarch aee/size class, with increasino; bare stems and spreading, but not taller, plants. It would appear that aerial d\iiamics of the crown of black sage- brush plants influence mound height. W'itli the senescent age/size class, adivergence 19921 Black Sa(;ki51u sii Dkmockapiiv 319 Table 5. Mouiul characteristics in relation to a classes of Aiicinisia noia. Illustrati's tliat liuige with age/size classes of shrubs. ound characteristic; Ml ound Litter 1 \'renni; il Cl leatgrass Black saijelirush DiaiiK ■tcr gnwtli classes Heigiit Max Mm Co\er Depth Weight g' iuss deusitv cover Number (cm) (cm) (cm) {%) (cm) (g) (per mound) (%) Samples Seedling 0 0 0 0 0 0 0 0 1 Young plant 2-5 fiO 30 5-10 0.5 40 0 2 6 Nhiture 5-15 SO 40 40-60 1-1.5 4S() 2.0 15 76 Patriarch 10-15 100 60 SO 2-3 690 2.S 12 21 Senescent 10-15 100 60 SO 2-3 720 2.1 60 15 Dead 10-15 100 60 SO 2.5-5 970 6.4 5 6 T.\BLF. 6. Mean nitrate level (mg/kg) of soil at the stem, canop\' edge, and onts in relation to maturit\- classes. Buckskin Mountains, Ne\ada.'' the c;uu)p\ ol black sagebrush plants Age/size class Location ' Stem Canopv Outside Age/size (ppnv) (ppm) (ppm) class mean' 4.7 h 4.3 hi 4.1 hi 4.4 d 6.6 g 5.5 g 4.0 1 5.4 c 10.5(1 12.0 b S.Oe 10.2 a 13.2 a 11.3c 7.0 f 10.5 a S.4 c 7.0 f 7.1 f 7.5 b 8.7 a S.Ob 6.0 c Young plant Mature Patriarch Senescent Dead Mean location 'Means followed by the same letter are not significantly different at the .01 le\el of probability as detennined by Unncans .Multiple Kange test. '■-Means of location followed b\' the same letter are not significantK' ilifTerenI at the .01 le\el of probability as determined by Duncan's Multiple Hange test. Mi-ans of age/size cliisses followed bv the same letter are not significantly different at the 01 le\cl ol prnbabilit\ as delermin.-d b\ Duncans Multiple Range lest. ill lu'ii);iceous species composition on the mounds occurs (Table 5). Some mounds become densely covered with cheatgrass as i)lack sagebrush plants become senescent antl others support colonies of squirreltail. After the black sagebmsh plants die, litter weight continues to increase and litter changes in appearance. Litter under dead plants is com- posed of stringN' bark fragments, and indixidual black sagebrush lea\es cannot be distinguished in the litter. Soil Nitrate Le\els Surface soil nitrate le\els were higher beneath shrub canopies than in the interspace (Table 6). Levels were highest next to shrul) stems. Nitrate le\e]s beneath the canop\' rose as age/size classes of black sagebmsh indicated older plants and moimds. This is in itself an indication that age/size classes actual]\ do reflect increasing age. The development of xer- tical and horizontal patterns in soil nitrogen, attributed to the localization of litter fall beneath the canopies of desert shrubs, has been documented by the research of N. E. West and co-workers (Charley and West 1977, West and Skujins 1977, West 1979). Nitrate lexels of sur- face soils dropped significantK (F < .01) once the black sagebmsh plants died. Nitrate le\els in surface soils at the edge ol slimb iiiouiids incn\ised with apparent increasing age of black sagebrush j^lants and mounds. These areas cor- respond to the micro-topoedaphic situation described as c()[)pice benches by Eckert et al. (1989) for shmb mounds in big sagebru.sh com- munities. ApparentK the increase in soil nitrate n^sults from leaching (rom the mounds. Once black sagebrush ])lants are dcatl and grasses doiiiinate the iiiomid. soil nitrate le\els decrea.se. Mounds and Black Sagebrush CommunitN Structure We did not find grass-dominated inounds or grass-dominated mounds with black sagebmsh seedlings. We did note the remains of mounds that appeared to be eroding awa)'. Apparently, 320 Great Basin Nathhallst [Volume 52 mounds are dvnamically formed and eroded in relation to the establishment and eventual death of black sagebrush plants. The failure to find grass-dominated mounds may be a function ol herbivoiy- by domestic livestock [sheep, feral horses {E(j{ius cahallus), and black-tailed jack- rabbits {Lcpiis californicus)]. Grass-dominated mounds nia\- fail to persist since grasses cannot maintain mounds because of leaf fall andcanop)' structure differences compared with black sage- brush plants. The onK' patchy vegetation encountered in the communities was groups of rabbitbrush plants. Perhaps rabbitbinish increases after relatively short-lived squirreltail plants die or are reduced h\ grazing. In an adjacent liig sagebmsh commimit)' we pre- \iously determined three episodes of seedling establishment at 12, 42, and 57 years before 1985 (Young et al. 1989). Plant ages were clus- tered around these apparent establishment dates. The clusters mav represent periods of desirable climate for seedling estabhshment or a single season when establishment occurred; they may also represent variabilitv in growth ring deposition or recognition. The classes we constnicted in this study are much too broad to pinpoint this t)pe of epi.sodic stand establisli- ment for black sagebrush. Perhaps black sage- bmsh conununities not renewed catastrophicalK b)' wildfires onh require stand renewal at such low levels (5% of the stand, standing dead plants) that our one seedling sampled is suffi- cient for conmnmit^' regeneration. LlTERATUHE ClTED B1':kti.f., a, a. 1960. A stiid\- of say;c!)nisli. Bullc-tiii 3fiS. Agricultunil ExpciiiiKMit Station, Uni\'rrsih ofAWomiiiu;, Liiramic. BuxiNCS. W. IX 1945. The plant a.ssotiations ofthc Carson Desert Hegion. We.sti-ni Xexada Bntlcr Ihiixcr.sih Botanical Studies 7: 89-12.3. BL/Msokll, J. R, AND R. C. HOLMCHKN 1984. Managing Intennountiiin rangeland.s — salt desert shrub ranges. Cencral Teclinical Report I NT- 163. Forest Senice, USD.'K, Internionntiiin Forest and Range E.xperinient Station, Ogden, tJtali. 52 jip. Cll.AKi.KV. J. L.. AND N. E. Wkst. 1977. Micro patterns of nitrogen. Mineralization activit)- in soils of some shrub dominated semi-desert eeo.s\ stems of LItali. Soil Biol- og)' and BiochemistiY 9: 357-.365. EckKKT. R. E., Jk . F. F. Peterson, M. K. \\'aku W. H. Blackbuhn, and J. L. Stephens. 1989. The role of soil-surface moipliologv in the function of semiarid rangelands. Ne\ada Agricultural E.xperiment Station Bulletin TB-89-()l. Uni\ersit\ of Ne\ada. Reno. Evans. R. A., and R. M. L()\ k 1957. The step-point method ot sampling. A practical tool in range research. Journal of Range Management 10: 20(8-212. HrDsoN. D. M., AND W. M. Oriel 1979. Geologic map of the Buckskins Range, Nevada. Map 64. Nevada Bureau of Mines and Geologv; Mackav Scliool of Mines, Uni- versity of Nevada, Reno. LiiGASKl. T R, AND J. A. YOUNC, 1988. Utilization of LANDSAT thermatic mapper data and aerial photog- raph) ior mapping the geolog>', soils and vegetation assemblages of the Buckskin Mountain Ranges, Nevada. American (Jongress on Suneving and Map- ping and American Societ\ for Fhotogrammetn' 1988: 21,8-227. Neter, J., AND W. VVasseh.vian. 1974. .A.ppliet! linear sta- tistical models. Rich;ird D. Irwin. Inc. Pkofeett, J. M., ]\\ . \ND B. 11. Phofeett 1976. Stratig- raphy of tlie Tertian ashflow tuffs in the Yerington district, Nevada. Ne\'ada Bureau of Mines and Geolog)- Report 27. Mackay School of Mines, Unixersitv of Nevada, Reno. 28 pp. We.st. N. E. 1979. Formation, distributicju. and function of plant litter in desert ecosystems. Pages 647-659 /;; R. A. Pern and i). W. Goodall, eds., Aridland ecosvs- tems: stnicture, functioning and management. Vol. I. International Biological Programme 16. Cambridge University Press, London. West, N. E., and J. Ski;jins 1977. The nitrogen cvcle in North American cold-water semi-tlesert ecos\stems. Ecologia Plantarum 12: 45-.53. Yol N(; ]. A., AND R. A. Enans. 1986. Erosion and deposi- tion of fine sediments from pla\'as. Joiunial of Arid En\ironments 10: 10^3-115. YouNc;. J. A., R. A. Evans. .\nd D. E. Pai.M(,)i:ist 1989. Big sagebrush {Artemisia tiidcntdfii) set-d production. Weed Science .37: 47-53. YoiNc, |. A., and F. Tipton. 1990. Invasion of cheatgra.ss into arid environments of the LtJiontan Basin. Pages 37-11 in E. D. McArthur, E. M. Romney, S. D. SmiU, and P. T Tueller, compilers. Proceedings of the Svni- posium on Cheatgrass In\;ision, Shrub Die-off, and Other A.spects of Shrub Biolog\ ;uid Management. {General Technical Report INT 276. Forest Senice, USDA, Ogden. Utah. ZvMORA, B., AND P. T TiEi.i.ER 1973. Artciiiisifi (irhiisnild. A. loii'^ilolxi, and .A. mnd habitat tvpes in northern Nevada. (Jreat Basin Naturalist 33: 22.5-242. Rrniiid 21 Chiohcr Ih)yi Accepted lU September 1992 Cireat Basin Naturalist 52(4 K pp. 321-52' MUSHROOM CONSUMPTION (MYCOPIIAGY) BY NORTH AMERICAN CER\ IDS Karen L. Lai iiR'hhaii'jii and I^ln'Iip j. Unless Abstiuct. — Nati\c miishrooms pla\ iui iiriportaiit. tli()uu;li olteii uiulerc'stiinatetl. role in deer elk. and Ciiribon diets in Nortli America. Mushrooms are often noted as an unusual or anomalous food in the diets of'eenids; \et the\- often dominate diets in the late summer and tall in forested areas of western North America and throusrhout the \'ear in tlie southeiLsteni U.S. Mushrooms are particularh' high in protein ( 16-19% ). phosphorus (a\ erage 0.759f ). and potassium (a\erage 2*^ ). Also, mushroom production is generalK' greatest in tall Tlieic^toic. th('\ are a liigliK nutritious lood in late se;LSon when other nati\e forages ma\' marginallv meet basal nutrii'ut recjuirements of ungulates. Kci/ words: ctirihoii. aTiid. deer. diet. dk. iin/<(ij)liii!^i/. iitiislirooiii. iiiihitidii. nnniiKint. \\'ildlife scientists ha\e lon^ recognized that certiiin higliK' nntritious, "bonus" foods fre- cjuently contribute significanth- to animal wel- fare though their contribution (%) to the diet nia\' be small (e.g., acorns, mushrooms, and mestjuite beans). By seeking out these high- ( [ualits' but generalK- scarce or ephemeral foods, li(n-bi\ores can balance nutrients against lower- (jualit\' forages that are more abundant. Natixe nuishrooms ha\'e often been recorded as a "bonus " food in the diets of deer, elk, and cari- bou in North America. However, their contribu- tion to cenid nutrition is not commonh' miderstood. The term "mushroom" refers to the flesh\ fruiting bod\ (sporocarp) of mam' species of fungi. Mushrooms are technicalK" not "plants." The\' belong to tlie kingdom Mxcetae under the fi\e-kingdom classification system (Whittaker 1969). The priman' mushroom-producing fungi are in the group called Basidionncetes, but man\ mushrooms eaten b\' wildlife, including morels, are Asconncetes. Mushroom produc- tion is triggered when species-specific rec^uire- nients of minimum temperature and moisture conditions are met (Smith and Weber 1980). Mushroom consumption (mvcophag)) has been recorded for man\' wildlife species in North America. Mushrooms are eaten b\ ungu- lates (e.g., deer and elk), small manunals (e.g., squirrels and armadillos), as w(>ll as birds, tur- tles, and insects (Miller and Halls 1969, Fogel and Trappe 1978, Martin 1979). Mushrooms ha\e long been recognized as an important com- ponent of small mammal diets (Fogel and Trappe 1978). Howexer, nuishrooms are seldom considered a significant component of cerxid diets even though the\ ha\e been anecdotalK recorded as a "preferred" food item, l^iscount- ing mushrooms as an important dietan conijx)- nent ma\stem from a misunderstandingol their nutriti\-e \alue. The piuposes of this re\iew are to (1) assess the contribution of mushrooms to cenid diets, (2) summarize the known literature on the nutritixe \alue of nuishrooms to ungu- lates, and (3) assess the im[)lications of nncoph- ag\' to liabitat selection and iiuli-itional ecologv contriihition of mush1u)()ms to Deer. Elk. ani3 Cai^ibol Diets Mushroom (lonsumjition b\ Deer Mam stu(li(^s haxc recorded mushrooms in diets of both mule {Odoroilciis hcinioiuis) and white-taikxl (Odocoilciis vir^inianii.s) deer (Table 1). Diet composition estimates range from a trace to a majoritx' of the diet. On the up[)('i- limit. 71.2% mushrooms, on a fresh- weight basis, were recorded in fall deer diets in .Mai)ama (Kirkixitrick et al. 1969), 65.8% in Augu.st diets in Arizona (Hungerford 1970), and 59.59f in .August diets in Montana (Loxiuis 1958). ^Range Science Department. Utah State University', Logan. Utah S4.322-.5230. "Present address: Range and WildHfe Management Department. Te,\a.s Tech University l.nhbock. 'Pi-xas 79409-212.5. 321 322 Great Basin Naturalist [Volume 52 Table I. Proportion of mushrooms in deer, elk, luid caribou diets in North America a\eraged o\er season''. Species State or Province (Vegetation t>pe) ^ % of diet Spring Summer Fall \\ 'inter Kind of data' Source' Mule deer (Odocoileus hemionus) Colorado ( spruce/fir/pine forest) Montana (spruce/fn/pine forest) Utiili (dn' mountain meadow) Utiili (mature conifer forest) Utah (stagnated conifer forest) Utah (conifer forest/oak woodland) Arizona (mixed-conifer forest) California (chaparral-oak woodland) British C'olumbia (conifer forest) White-tailed deer (Odocoileun virginianiis) .\ew Brunswick (conifer/deciduous forest) Maine (pine-hemlock forest) Penn.svKania (clear-cut forest) Southeastern U.S. (oak-hickoiy-pine forest) Southeastern U.S. (mixed-pine forest) Southeastern U.S. (southern evergreen forest) X'irginia (eastern deciduous forest) North Carolina (oiik-hickor\'-pine forest) South Carolina (mLxed pine forest) CJeorgia (southern evergreen forest) Florida (southern evergreen forest) Florida (southern evergreen forest) Florida (pine-scmb oak forest) Alabama (southern pine-hiirdwood forest) Alabama (southern pine-hardwood forest) Louisiana (pine-bluestem range) Louisi;ma (pine-hardwood forest) Louisiana (clear-cut forest) Texas (pine-mixed hardwood forest) Oklahoma (oak savannah) Wisconsin (northern hiirdwood forest) Miiniesota (northern hardvvood forest) South Dakota (pine forest) South Dakota (pine forest) Elk (Cervus eUiphus) X'irginia (eastern tleciduous forest) Saskatchewan (pine forest) Saskatchewan (mixed forest) Utah (diy niountiiin meadow) Utah (mature conifer forest) Utah (stagnated forest) California (Pacific rain forest) Caribou (Ratif>ifer tarandus) Newfoundland (conifer forest) Northern Canada (conifer forest) Northern Canada (boreal forest) Alaska (spnice forest/tundra) Alaska (spruce forest) - 0.3 - - Obs.(% bites) 31 0.0 12.1 0.0 0.0 Rum. (% vol.) 21 - 7.0 - - Obs. (% mass) 10 - 15.0 - - Obs. (% mass) 10 - 14.0 - - Obs. (% mass) 10 - 5.4 9.3 - Obs. (% ma.ss) 4 - 16.4 - - Obs. (% time) 16 - - - <1.0 Rum. (%vol.) 20 0.0 0.0 13.0 4.0 Rum. (7c vol.) 8 13.7 6.7 9.1 Rum. (% m;rss) 26 0.0 0.0 45.0 0.0 Obs. (% mass) 9 1.6 0.2 0.8 4.5 Obs. (% time) 14 2.1 19.8 8.4 6.2 Rum. (% vol.) 12 0.4 15.6 8.6 4.9 Rum. (% vol.) 12 0.6 16.4 5.4 3.2 Rum. (^c vol.) 12 0.0 40.0 2.5 0.0 Rum. (% vol.) 19 0.0 10.6 7.0 0.0 Rum. (% vol.) 19 0.2 33.4 2.6 10.7 Rum. (% vol.) 19 0.0 9.7 9.0 13.8 Rum. {'7c vol.) 19 1.4 10.4 26.7 13.2 Rum. (% vol.) 19 - - - 9.2 Rum. (% vol.) 11 - - - 25.2 Rum. {7c vol.) 11 0.0 71.2 0.5 17.4 Rum. {9c vol.) 19 7.3 - 4.8 0.8 Rum. {% vol.) 1 0.5 1.5 3.5 <0.5 Obs. (%■ bites) 28 - 0.4 1.9 0.7 Obs. (% bites) 29 - <0.1 2.1 0.2 Obs. (% bites) 29 3.0 34.0 1.0 7.0 Rum. (% mass) 25 0.0 0.0 4.3 1.0 Rum. (rel. freq.) 30 - 2.0 - - Rum. (% vol.) 22 - - <1.0 0.0 Rum. (% vol.) 2 0.0 4.0 2.1 0.0 Rum. (9c vol.) 15 - 0.7 0.5 <0.5 Rum. [9c vol.) 23 1.0 Rum. (%vol.) 3 - 5.3 - - Rum. (% mass) 17 - 4.2 - - Rum. (% mass) 17 - 4.2 8.3 - Obs. (% mass) "" - 18.7 55.7 - Obs. (% mass) "" - 18.4 55.4 - Obs. (% mass) "* - - 0.3 - Obs. (% time) 13 0.0 25.0 12.0 0.0 Rum. {9c vol.) 5 - - - 0.4 Rum. (% vol.) 24 - 1.2 - - Rum. {9c vol.) 18 0.0 12.0 10.0 2.0 Obs. (% vol.) 6 - - 45.0 - Rum (% vol.) 27 \\ cliLsli (-) listed a.s % in diet me:m.s no data were availablf . 'General description.s given by authors or vejretation area according li> Aldruli 19(i:). 'Obs.= observational data, Hnni.= rumen contents. "Key to references: (l)AdaiMS 1959; (2)Aldous and Sniitb 19.%; i3IHalduin and I'alton 193,S; (4U3eale and Darbv 1991; (.5)Bergenid 1972: Ui'Boertje 19S4; (7)Collins 1977; (.S)Cowan 1945; (9)Crawford 19S2; ( l{))Descbamp et al. 1979; ( 1 1 )Ilarl()\v J9fil ; ( 12)IIarlow and Iloojx-r 1971; (1.3)Harper 1962; (14)Healv 1971; (15)Hillandriarris 194.3; (16)IIungcrford 1970: (17)IIunlI979;(lS)Kels;illH)6S(19*Kirkpatricket;il. 1969;(2())I^opoldetal.l95l;(21)Lovaas 195S;(22)Mc<;;affen- et al. 1974; (23)Scliencket al 1972; (24)Sc()tter 19R7; (25).Sliort 1971 ; (2R)Skinn rumen becan.se of chitina,se activitv bv rumen microbes, although there mav be an adaptation period necessaiy to obtain adecjuate levels of chitinase activitv (Clieeke 1991). The abilitv of rumen microbes to degrade the p-glncans in lungal cell vxalls is unkiumn. Tlie in vitro digestibilitv of nnishrooms is ven high r(4ative to other ungulate forages (Table 2) and mav exceed 90% in some cases. Consequentlv, identification of nnishrooms in fecal analvsis is rare (Boertje 1981). iMl'LICATIOXS OF MY( :()IM lACV liV Di:kh AM) Ei.K To conchid(^ this discussion it is lair to ask. What difference does it make if dcc\\ elk. or caribou eat nnishrooms or not? Mvcophagv bv cenids mav be important for several reasons. First, nnishrooms niKk)ubtedlv make an im|:)ortant, though s])oradic. contribution to cenid nutrition in musli room-rich environ- ments. Mushrooms are highlv preferred and nutritions foods for cervids, particularlv in late snminer and fall in forested areas of western North .'\mei ica and throughout the vear in the Southeast. .Mushrooms mav be a particularlv im[)ortant protein and phosphonis source in late season when main forages vield onlv enough digestible d\y matter to meet basal energv re(iuirements (Short 1975, Blair et al. 1984). Therefore, even a fev\- bites of mnshrooins bv an herbivore may contribute substantiallv to meet- ing the nutritional requirements and helping to balance nutrients obtained from other forages of (^uite different composition. 326 Great Basin Natuhai.ist \\<>\ iiiiic o2 Second, mushrooms may attract herbivores to mature and stagnated forest areas that might otherwise go unused as foraging areas (Rasirius- sen 1941, Collins et al. 1978, Warren and Mys- terud 1991). Additionally, mushrooms may become an important dietaiy supplement when herbi\"ores are forced to seek densely forested areas for protection from biting insects or pred- ators (Bergemd 1972). Mushroom production is usucilK" greatest in dense forested areas, in part because mushrooms do not require sun- light for o;ro\\th. Finallw fungi pla\' an important s\nibiotic role in m\corrhizal relationships with several conifer species, including ponderosa pine (Kotter 1984). Since the spores of fungi are apparentK' not destroved in the nmien, herbi- \"ores ma\' sene as \ectors for fungal spores to initiate nncorrhizal associations (Fogel and Trappel978). Literature Cited .\dams. W. H. 1959. Chaccolocco deer range andvsis and management implications. Proceedings of the Sonth- eastern Association ot Game and Fish Connnissioners 1.3: 21-;34. .\LDOLS. S. E.. and C. F. Snuth 193S. Food habits of Minnesota deer as determined bv stomach anaksis. Transactions of the North American W'ildhfe Confer- ence 3: 7.56-7.57. .■\1X)RICI1, J. W. 1963. Geographic orientation of .Americiui Tetraonidae. Jonnial of Wildlife .Management 27: 529- .545. Baldwin, W. P.. and C. R Pxtton 193S. A prelinnnan stndy of the food habits of elk in \ 'irginia. Transactions of the North .American Wildlife Conference 3: 747- 755. Bkalk. D. M.. and N. W. n\i!nv 1991. Diet composition of mule deer in monntain brush habitat of southwest- ern Utali. Publication No, 91-14. Utah Division of Wildlife Re.sonrccs. Bf.IU;krid. a. T. 1972. F(xhI habits of New tonntlland c.ir- ibou. Journal of Wildlife Management 36: 913-923. B]l csTAD, A. J., AND A. \; DAi,in\n>i.iv 196S, Beef heifers on Ozark ranges. Bulletin No, S7(), Missouri .\i:;ricul- tural Exjx'riment Station. Bi.AU^ R, M,. R. Ai.coNr/, AND 11. F. Mohkis 19S4, Yield, nutrient conipo.sition. anil ruminant iligestibilit\ of fleshy fungi in southern forests, journal of \\ ildlife Management 4S: 1344-1.3.52, BoKHTji:, R. D. 19S1, Nutritional ei-ologxof die Dcn.ili caribou herd. Uupubli.shcd master's tliesis, Uui\crsit\ of .Maska, Fairbanks, . 19S4. Seasonal diets of the Dcnali c.uibou licrd. .\laska. Arctic 37: 1(S 1 - 1 65 . CllANc:!',, S. T. 19S0. Mushrooms as human food. Hioscicucc 30:399-401, CllKKKl-. P R. 1991. .\pplieil animal nutrition M.Kiuill.ui Publishing Co.. Inc.. New York, Coi.l.ixs, W, B, 1977, Diet composition ami actixities of elk on diflerent habitat .segments in the lodgepole pine type, Uinta .Mountains, Utah, Performance Report for Federal Aid Project W-I0.5-R-2-14, Publication No. 77- IS, Utali Division of Wildlife Resources. Coi.i.iNs W, B„ P J. Ukness. AND D. D. Austin. I97S. Elk diets and activities on different lodgepole pine habitat .segments. Journal of Wildlife .Vlanagenient 42: 799-810. Cowan I. .M. 1945. Tlie ecological relationship of the food ol the (Jolunibian black-tailed deer, Odocoileua lu'inionus cnhimbianus (Richardson;, in the coast forest region of .southern Y'ancouver Island, British Columbia. Ecological Monographs 15: 111-1-39. Cr.w FOHD. H. S. 1982. Sea.sonal fofxl selection and digest- ibilib, by tame white-tailed deer in central Maine. Journal of Wildlife Management 46: 974-982. Ckisan. E. v., and a. Sands. 1978. Nutritional value. Pages 137-168 in Edible mushrooms. Academic Press. New York. Dkschamp J. A.. P J. Ukness and D. D. .Austin 1979, Summer diets of mule deer from lodgepole pine habi- tats. Journal of Wildlife Management 43: 1.54-161. Dixon. J. S. 1934. \ stud\ of the life histon and food habits of mule deer in CiJifornia. California Fish and Game 20: 31.5^3.54. Fogel. R., and J. M. Trappe 1978. Fungus consumption (mv'cophagv) bv small animals. Northwest Scienc-e 52: 1-31. R\RLO\\. R. F. 1961. Fdl and winter foods of Florida white- tiiiled deer. Quarterlv Journal of the Florida Academy of Science 24: 19-38. Harlow. R. F.. and R. G. Hooper 1971. Forages eaten by deer in the Southeast. Proceedings of the Southeastern Association of Game lUid Fish Commissioner 25: 18-46. Harper, J, .A, 1962. Davtinie feeding habits of Roosevelt elk on Boves Prairie. Ciilifomia. Journal of Wildlife Nhmagement 26: 97-100. Healv \\'. M. 1971. Forage preferences of tame deer in a northwest Penns\lvania clear-cutting. Journal of Wild- life Management 3-5: 717-723. IIii.L, R. R,. AND D. H.\RRls. 1943. Food preferences of Black Hills deer. Journal of Wildlife Management 7: 233-234. Hi ngerford, C. R. 1970. Response of Kiiibab mule deer to management of summer range. Jouniiil ot Wildlife MiUiagement 34: 152-162. Hi NT. H, M, 1979. Sunnner. autmnn. and winter diets of elk in Saskatchewan. C^iuiadian Field Natin-alist 93: 2S2-2S7. fl Ki'.KNS M. H. I97S. .\ninuil feeiling lUid nutrition. Ken- dall Hunt Publishing Compan\. Dubuque. Iowa. K\i;\i\ G. I. 196vS. Reindeer fodder ivsources. In P. S. Zhigunov, ed.. Reindeer husbandiv. l".S. Department of C'onuiierce, Springtu^d. N'ii^ginia. K,i 1 sall, J. P. 196vS. The migraton IxuTen-giound c;uibou of (Canada. Queens Printer. Ottawa. Ontiuio. Cimada. IvIKKrATRK K. R. I... ). P. FONTENOT. AND R. F. IL\RLO\\. 1969. Sea.sonal changes in nunen chemical cx)mpo- uents as related to forages (.x>nsuined b\ wiiite-tiiiled deer of the Southeast. Transactions of the North .Amer- ican Wildlife and Natural Resouixvs Conference ;34: 22VV 2;vs. IvonKK, M. M. 19S4. Formation o( pondeaxsa pine t>etoni\wrrhizae after inoculation with feces of tassel- eannl squirrels. M\wlogia 76: 75S-760. ki 111 D H, C. 1973. FiHxls eaten bv Rix.>k\ Mountiiin elk. jomu.il of Range Management 26: 10(>-113. 1992] MVCOI'IIACYBVCEKMDS 327 l.ioi'OLi) A. S..T, Hi\KV H. M( C:\iN.ANn I.Tkvis 1951. The Jawbone dccf licid. ( i.iiiir Bulletin No. 4, Depart- ment ol Natnral Kesoniccs, I )i\isi(in ol l''isli and Cl.iine Connnision. U)\\\S. A. L. iy5(S. Mnle deer lood lialiiK and lan^e nse. Little Belt Mountiiins, Montana |oninal ol Wildlile Miuiagement 22: 27.'>-2S2. M.MrriN. M. M. 1979. Bioelienncal implications of insec't niNCopliagN. Biological Be\ic\\ 31: 1 21 M(:C.\FFEHV. K. B., J. Tk ANKT/KI AM) |. FlIJ 111 H \ 1971. Smnmer foods ot deer in nortlu^rn Wisidnsin. |omnal ofWildlile Management .IS: 215-219. Mll.LKK. II. A., AM) L. K. 11A1.1..S 1969. Meshv fnngi eom- monlv eaten b\- southern wildlife. IJSDA. Forest Ser- \'ice. Research Paper ,S()-49. VIooke-LaNDF.CKF.H, E. 19S2. The f'undamentiils of the Fungi. Prentice-Hall, Inc.. Fnglewood Cliffs. New Jersey. PaLLESEN. J. D. 1979. Nutritive \alue of mule deer and elk diets luid forages on lodgepole pine summer range in Utah. Unpublished master's thesis, Ut;ili State Univer- sity, Logan. Peck, C. H. 1895. Report of the New York state botanist. Page 113. Reported f/i L. B. Mendel, 1989, The chem- ical composition and nutritixe \alue of some edible American fimgi. .\merican [onrnal ot Plnsiologv 1: 22,5-235. R\SMUSSEN. D. I. 1941. Biotic communities of the Kaibab Plateau, Arizona. Ecological Monographs 11: 229-275. SCHENCK. T. E., R. L. LiNDEK, AND A. H. RiCHARDSON 1972. Food habits of deer in the Black Hills. Part II: Southern Black Hills. Bulletin No. 606, South Dakota Agriculturd Experiment Station. ScoTTER. G. \V. 1967. The winter diets of barren ground c;iribou in northern Canada. Canadian Field Natm;ilist 81:3;3-39. Short H. L. 1971. Forage digestibilitx and diet of deer on southern upUuid range. Journal of Wildlife Manage- ment 35: 69.S-706. . 1975. Nutrition of southern deer in different sea- sons. Journal of Wildlife Management 39: 321-329. Skinner, W. R., and E. S. Telfer. 1974. Spring, sunnner. and fall foods of deer in New Bnm.swick. |ournal ol Wildlife Management 38: 210-214. Skoog. R. O. 1968. EcologN- of the caribou in Alaska. Unpublished doctoral dissertation, Uin\<-rsit\ of Cali- fornia, Berkelex. Smith. A. H., and N. S. Weber 1980. The nnishroom hunters field guide. University of Michigan Press. .-Kun Arbor SvR|Al,\-y\ isi L. 19S6. Improvement of natural pasture utilization by sheep. In: O. Guduumds.son, ed., Grazing research at northern latitudes. Plenum Press/NATO, New York. Ti.\ IS L. 1952. .Autumn loods of cliipniunks and golden- mantled ground S(juirrels in the northern Sierra Nevada. Journal of Mannnalog\^33: 198-205. Tim I R. E., AND A. Martin 1986. Deer ;uicl cattle diet overlap on Louisiima pine-bluestem range. Journal of Wildlife Management 50: 707-713. Tiiiii, R. E., II. F. Morris. Jh . and A. T Harhei, 1990. Nutritional (jualit)' of deer diets from southern pine- hardwood forests. American Midliuid Naturalist 124: 41.3-417. Tri.ka, M. |. 1977. Distribution and ntili/ation of carbohv- drate resenes in range plants. In: R. E. Sosebee, ed., RangeUuid plant phvsiologv. Societ\- for Range Man- agement, Denver, Colorado. Ullrev, D. E., ET AL. 1973. Calcium re(jnirements of wetined white-tailed deer fawns. Journal of Wildlife Mtmagement 37: 187-194. Urness, p. J. 1985. Managing lodgepole pine ecosystems for game and rtuige values. In: Lcxlgepole pine: the species and its management. Symposium Proceedings. Cooperative E.xtension Senice, Washington State Uni- versity, Pullman. Van Soest. P. J. 1982. Nutritional ecolog\ of the ruminant. Cornell University Press, Ithaca, New York. Van Vreede. G. T. 1987. Seasonal diets of white-tailed deer in south-central Oklalioma. Unpublished master's thesis, Texas Tech UniversiK, Lubbock. Wali.mo. O. C, W. L. RJ'^celin. and D. W. Rf:iciiEin". 1972. Forage use b\' mule deer relative to logging in Colorado. |onrnal ofWildlile Management .36: 1025- 10.33. Warren, J. T, and 1. Mvsterud 1991. P'migi in the diet of domestic sheep. Rangelands 13: 168-171. Willii\Ki:n R. II. 1969. New concepts of king(k)ms of organisms. Science 163; 1.50-160. Received 15 June 1992 Accepted 25 September 1992 Great Basin Naturalist 52(4). pp. 328-334 TERRESTRIAL VERTEBRATES OF THE MONO LAKE ISLANDS, CALIFORNIA Michat'l L. Mcirrison', William M. Block-, Joseph H. Jchl, Jr. '. and Liiinea S. Hall'^ .ABSTHAcr. — \\\' compared \ertebrate populations between the two major islands (Paoha and Nes^it) in Mono Lake, Calirornia. and tlie atljac(^nt mainland to further elucidate the mechanisms underlying island colonization. Deer mice {Peroini/sais maiticuhitn.s) iuid montane voles (Microtus iin>nt(iniis) were captured on Paoha, but only deer mice were captnred on Negit. In contrast, eight .species of rodents were captured on the mainland. Oxerall rock^nt abundance on Paoha and the mainland was similar, but on Negit it was about three times greater than on Paoha or die mainland. Adult deer mice from Faoiiawi're significanth' (F < .05) smaller in most e.xternal bodv characteristics than m;unland mice. Coyotes (Canis latniiis) and one or two species of lagomoiphs were observed on the islands and the nuiinland. No amphibians or reptiles wt-re found on the islands; both occmred in low numbers on the nnrinland. Ratting and hinnan transport are probable means of colonization for mice and voles. Tile occiu'rence ot co\otes on the islands max have moditied liistoric predator-pre\' relationshi|is. and thus the population of rodents and lagomoiphs. Kcij iLonls: Moiiii Lake, islaiids. coloniziilidii. Peromyscus maniciilatns, Microtus montanns. /c//if/ /i/iV/gc. Lslancl animal popukitions ha\c attracted much scientific interest because they sene as natural experiments for the study of cok)niza- tion, dispersal, extinction, competition, and otlier biological processes (MacArthur and Wilson 1967). Because islands are stnall and isolated, populations inhabiting them are more N'ulnerable to stochastic ewnts than their main- land counteiparts. Most previous studies of island zoogeogra- phy ha\e emphasized patterns of island occu- pancN', morpholog\', and genetics of restricted subsets of the islands' fauna (reviewed b\' ]^'lt()iK>n and Ilanski 1991 ). Our goals were to couipare island and mainland \eii:ebrates of Mono Lake and the surrounding Mono Basin, California, in light of natural and human-infhi- enced processes. This area was of interest because no thorough sunevs had been con- ducted on the islands of this large saline lake, and because of possible changes in local ecolog\- as.sociatcnl with falling lake levels from water diversion lor human consumption. Mono Basin and Islands Mono Basin is the In drolotjic drainage basin for Mono Lake. The l^asin is surrounded by the Sierra Ne\'ada to the west and the Great Basin ranges to the north, east, and south. Mono Lake, estimated at 500, 000 vears of age, is one of the oldest lakes in North America. Because no water naturalK flows out of the basin, and because of long-term evaporation coupled with water diversion, the lake's salinitv' is aliout 2.5 times that of the ocean. In October 1986 the surface area of the lake was about 177 knr (Mono Basin Ecosvstem Stud\ (xnnmittee 1987). There are t^\■o major islands in the lake: Paoha Lsland at about 7.7 km' and Negit Island at onK about 1.3 knr (Fig. 1). Paoha formed liom volcanic activitv and an uplift of lake sedi- ment some time between 1723 and 1850 A.D. Negit formed as a result of a series of eruptions beginning about 200 A.D. (Mono Basin Ecosys- tem Studv (>'oiMmittee 1987, U.S. Forest Senice 1989). ill72(l ,uhI Willi. ■ \1. mill. nil Ki n<-|iartiiiriil.,rK(m'sti-\^UKl Hc-soiucc Maiui<;riiic-iil, Unu3 km (Mono Basin Ecos\s- tem Stud) Committee 1987: Figs. 1.3 and 6.1). Howexer, no mainland coiniection with Negit existed since the formation of Paoha until the late 197()s; the next most recent laud bridge apparenth- occurretl about 500 xcars before present. During our stud\- in 1990-91, Negit was separated from the mainland In' sexi'ral lumdred meters of nuidflats and a fex\' meters of shalloxx' xx'ater; this area is referred to herein as the land bridge. ^^'eknox\■of onlxtxx'opnnious small mauunal trapping efforts on the islands. In 1975 W. M. Hoffmann (unpublished report) captured no small nuunmals on Paoha in one night of effort. |. IL Harris (personal conununication) cap- tured deer mice {Peromyscus maniculatus) on Negit during sexeral dax's of trapping in the earlx' 198()s. One of us (fRp has nuuU^ repeated xisits annuallx to the islands since 1980, making xisual obsenations, but not trapping. .\1I otlicr accounts of the islands" manunal hiunaare troui recollections of earlv settlers and local residents (e.g., Fletcher 1987. personal connnunication xxith JRJ). Study Akkas I'aoha Island can be dixided into txxo general X egetatixe /ones: a small (about 2 ha) spring-fed marsh along the southeastern shore, and the remaining nonmarsh xegetation. \egetation in tlu^ marsh is composed of rush (Junciis effusus), bullrush {Scii~})iis americanus), saltgrass {Dis- ticltlisspicata), foxtiiil {Hoirleiunjtibatum), and bassia {Bas-sia Iii/ssopifolia). Nonmarsh areas aic dominated bx greasexx'ood (Sarcohatiis vcr- inicuhitus) and hopsage (Grai/ia spinosa): sage- brush {Aiiemi-sid tridentaia) is present but rare. (brasses and herbaceous plants are scarce and concentrated in the marsh and one small (about 0.3 ha.) gnisslaud site located upslop- about 300 m 330 Great Basin Naturalist [X'olume 52 from the marsh. The grassland area is domi- nated bv exotic clieatgrass [Bronms tectoniin). Negit Island lacks any marsh \egetation and has no permanent freshwater. The upland is similar to Paoha e.xcept for more cover by sagebmsh. Dominant \egetation on the mainland plots is sagebmsh, rabbitbrush {CJinjsotlunnnus nausc- osus), bitterbmsh {Purshia triclentata), and scat- tered individuals of greasewood, curlleat maliogany {Cercocatyus k'difolitis), and desert peach (Pninns ai}ch'rso)iii). Vegetation in the basin was detailed b\- Burch et al. (1977). Soils are a loose mixture of sand, gra\'el, ash, and silt (Loeffler 1977). In 1990 trap lines were established to deter- mine species composition and approximate dis- tributions of small mammals on Paoha and Negit. Specific trap locations were based on ease of boat landing and proximit\' to the next nearest trapping location; adjacent trap lines were at least 200 m apart. In 1991 we systematicalK* established 10 fixed study plots (50 x 20 m) on Paoha Island and 5 on the adjacent mainland to compare mammals on the island and mainland; island plots were placed in the marsh (3 plots) and diy shrub vegetation (7 plots). All mainland plots were located to the north and northeast of Black Point on the northwest shore of Mono Lake. This location was selected because its vegeta- tion resembles the dominant \egetation on Paoha Island and represents a likeK' sovux-e for terrestrial animals. Methods Small Mammal Lixe-Trapping All traps used during this stud\' were large (7.6 X 8.9 X 22.9 cm" [3 x 3.5 x 9 inch]) Sherman live-traps. In 1990 trapping was done on Paoha Island on 27-29 April and 23-25 August, Negit Island on 27-29 April, and the mainland on 4-7 September. Trap spacings ranged fnjm 10 to 20 m and were based on axailabilit)- of vegetative coxer. Traps were baited with rolled oats and peanut butter and checked each morning for 1-3 davs depending upon weather conditions and thus access to the islands. Mainland trapping in 1990 was restricted to a marsh on the northern shore of the lake. Captures were identified to species, sex, and age and were measured, iriarked, and released at the trap location. Measurements between sexes and betAveen island and main- land populations of deer mice were compared using/ tests (Zar 1984:126-131). In 199 1 , within each plot on Paoha described abo\'e, 18 large Sherman live-traps were placed at lO-m spacings (1 row of 6 traps along each long axis of a pk)t). Each plot was trapped for a total of 54 trap-nights and da\s (i.e., traps were left open constantly for 3 days and checked both during the morning and in late afternoon) . Traps were baited and animals handled as in 1990. Mainland and Paoha traps were run 7 Mav-24 June. Trap lines were rim on Negit 4-5 August, as described for 1990. Data are reported here as the number of new individuals (i.e., excluding recaptures) captured per 100 trap-nights; we assume that this measure of capture success is an adequate index of actual population abun- dance. Indices of abundance were compared using chi-square goodness of fit (Ziu- 1984:40-43). Other Sune\'s During 1991, one 4.2-L (1-gal) can was placed near the center of each trapping plot. Cans were placed on all mainland plots and on six Paoha Island plots. Each was coxered with a wooden board raised 2-3 cm abo\e the can. Traps were am 4-17 da\s. Three additional traps were placed in the marsh on the southeast side of Paoha Island, this being the most likeK' location for shrews (Soricidae). Thus, six traps were placed in the marsh. All mainland pitfalls were opened 9-12 June; island traps were opened 7 Ma\'-4 June. A 1-m" area in an open location near the center of each plot was selected to determine the presence of mediiuii- to larger-sized mam- mals traxeling across the plot. The soil in a track plot was smoothed bx' hand and moistened xxith xxater; fine-grained sand or soil xxas added as needed. A can of chicken-flaxored cat foodxx'as secured at the center of each track plot. Each plot xxas checked dailv for three days for evi- dence ofxxildlife use. One-half of the studx' plots on Paoha and three mainland studx plots xxere used. Time-constraint sunexs of one-person-hour duiation each were conducted in all study plots. The species, date, time, location, and general xegetation tvpe for each obserxation xvere recordctl. Museum Records \\e obtained records for all xertebrates col- lected in Mono Basin from the Los Angeles 1992] Mono Lake Islands Vertebrates 331 T\iil.K 1 . Index ofabuiulance (iio./KX) trap-niijhts) for small niaimnals captured on stiicK plots on Paolia Island (n = 10 plcits and .idjaeent mainland (n = 5 plots). ;uid on Negit Island (trap lini's). Mono Basin, (-'alifornia. 1991.'' Species Paoha Island (trap-nights) Totd Total Total marsh nonmarsh island (108) (324) (432) 17.6 13.0 14.1 8.3 9.0 -S.8 9.3 4.0 5.3 5.6 0.9 2.1 Negit Island ( 120) Total mainland (.■342) Pcroini/sni.s uumicnlatiis Male Female Micmtiis iiioiitanus Pcmi^)i(itliiis panti.s Dipodoiiuis pauainintinits D. microps Pcroiiii/.srus hoi/lii Eutamiits minbntis Sp('n)to)>hilus hccclwyi Total 62.5 32.5 30.0 23.2 13.9 16.2 62.5 6.4 4.1 2.3 0.3 6.7 5.3 1.8 0.3 0.3 0.3 21.3 ■'Chi-srjiiare anaKsis: all comparisons between total marsli and total nonmarsli cm Paoli.i /' > .0.5; between P.iolia total island and \e0t Is Paoha and total mainland P >,0.5; and between total mainland and Ne^il I' ■ 1)1 1 P < .(X)l; l)et%veen total Counh' MiLseuni of Natural Iliston (LACMNH) and the Museum of Wrtebrate Zoolog)', UniversitS' of California, Berkele\ (MVZ). Although no records were available for the islands, data from the basin were sununa- rized to supplement published accounts of mainland \ertebrate sun'eys. X'oucher speci- mens were deposited at the M\"Z. Results Small \himmal Trapping Only deer mice and montane xoles {Microttis montanus) were captured on Paoha Island. Most voles were captured in the marsh; deer mice were also slightK' more abundant there than in dn' sliRib plots, but these differ- ences were not significant (F > . 1). The sex ratio of deer mice was sk'ewed toward males in the dr\' sliRib, but was about e\(Mi in the marsh (Table 1). Onlv deer mice were captured on N(^git Island. Nh)us(' abundance was ai)out 4.5 times higher on Negit than on Paoha (F < .05), and sex ratios were about e\en (Table 1). Eight species of small mammals wen^ cajv tured on the mainland plots in 1991. Cireat Basin pocket mice {Perognathus parvus), deer mice, and Panamint kangaroo rats (Dipodoinijs ))(i)ia)nintiiius) had similar relatixe abundanc(\s and were the onl\- species with abundances >5 indi\iduals/100 trap-nights). Except for the Great Basin kangaroo rat {Dipodomi/s microps), all species were captured rareK' (all at 0.3 ani- mals/100 trap-nights). Oxerall abimdance of small mammals on Paoha was similar to that on the mainland, but on Negit it was almo.st three times greater than that on Paoha (F < .001) or the mainland (F < .01; Table 1). Abundance of deer mice approximateK' dou- bled (F < .01) on Paoha betvxeen April (earl\ breeding) and August (end of breeding) 1990. Subadult males accounted for fiT'^'f of this increase (Table 2), wiiile subadult females accounted for onlv 67c. Total male and female abimdance was about etjual in April; the number of males caught increased b)' 63% and females onlv by 35% in Augvist, although the difference was not significant (F > .1). Nhile and female abundances of deer mice were similar on Negit in April 1990; no compa- rable August data were a\ ailable. Total abun- dance on Negit in April was 48% higher (F < .05) dum that on Paoha (Table 2). Adult male deer mice from Paoha weighed significantly less and had significantK shorter tails, feet, and tail :bodv-length ratios than main- land animals; bod\ and ear lengths were not different (Table 3). .Adult females from Paoha were significantK less hea\A- than mainland ani- mals and had smaller but not significantly dif- ferent a\(M-age measurements for other characters. Comparisons with Negit mice were not j)ossil)le because an insufficient number of animals were measured. Other Sun e\s Islands. — The six pitfalls in the Paoha marsh were nm for 13 da\s (78 trap-da\s) and captured 7.7 xoles/lOO pitfall-days; the three 332 Great Basin Naturalist [N'olume 52 TAIU.K2.Al.un(lancv(noyi()()trapMn,uhts)<.i7Vr<Hi(/.sr(/.s;;i^/;i/r((/r////.s captiiicdon Faolia Island. .Mono Lake, and atljaccnt mainland dnrinii 1990 iuid 1991. Adult male" Adult f( i-mde'^ Paoha Mainland Paoha Mi iiinli uid Characteristic X SD X SD X SD X SD Mass (gf 17.2 2.11 IS.S 1.29°° 18.1 2.29 19.9 2.80"" Hod\- length (mnO SI. 4 5.13 SI. 4 2..S7 79.4 6.50 Sl.l 3.18 Tail length (nnn) 64.5 4.32 67.1 5.;34° 66.4 6.85 69.1 6.34 Foot (nnn) 20.0 1.07 20.9 0.95°° 20.0 0.91 20.6 1.08 Ivir (mm) 17.4 J.OS 17.4 1.45 17.4 1.04 17.9 1.38 Tail/I)c)d\ 0.79 0.06 0.S2 0.07° 0..S4 0.07 0.85 0.07 ■■Saiiiple size = 50 indi\i(l tlu^ ba.sin lor a iiiucli longer period (Fletcher 1987). Western immigrants began making trips to the islands 1)\ the 1860s (Jehl etal. 1984, 1988, Fletcher 1987). A cliicken [GaUu.s galliis) and domestic lago- moiph ranch was established on Paoha in tlie late 187()s, a domestic goat {Capra sp. ) ranch was initiated in the 1896s (Fletcher 1987). and a mineral salts and health spa \entnre was attempttnl in the 194()s. Lagomoiphs raised c()mmerciall\ werc^ apparentK European hares (Lej)us sp.), but there is no exidence that these hares remained on Paoha after the earlv 192()s when the commercial operation ceased. A few goats suni\ed on Paoha until at least 1975 (Hoffman, unpublislied report) but were extir- pated b\ 1980. Thus, human moxxMueuts onto the ishinds \\(M"e li"e(|ucnt. and rodents, such as deer mice and \ oles, couki ha\e been inadxertentK traus- portcxl in the grain, ha\. and other it(^nis taken to support acti\iti(\s on the islands. We do no! know il natixc lagomoiphs were traiiportcd to th(^ islands In liumans. There is debate in the literature oxer the abilities of PcrojiKjscus. Microfiis. and other small mammals to coloni/e iskmds b\ s\\ iinming or rafting because the\ are not well adapted lor exposure to water (Redfield 1976, (^alhoiiu and Greenbaum 1991, Peltoneu and Hanski 1991). We haw no direct wa\- of (juantifxing the rela- tixe prol)abilities of inadxertent liuman trans- port xersus rafting. Ih)x\exer, the knoxxn and fre(juent histonof liuman xisitation and habita- tion tor commercial puq3oses during this cen- tun- results in a higher frecjuencx' of occurrence and less harsh means of possible transport than (k)es raiting due to Hooding (ncnts. (.'onfonnd- ing the present situation is the laud bridge or near land britlge. .Moxement across the land bridge to Negit, folloxx'cd bx swimming or raft- ing to I-*a()ha, is likelx more probable nox\- than historicalK'. The ab.sence of lizards on the islands is [)er- plexing. Iioxxexer, as there appears to be ample habitat on the islands, and species on the main- land are potentiallx good colonizers (sensit ("ase 1975, 1983). Hoxx'ex'er, mainland [)()puIations are small, as the elexatiou of the .Mono Basin is at th(Mipperendof the normal range for reptiles in the Sierra Nex'ada (summarized from Storer and Usinger 1968). Therefore, their chance of arrixal and persistence is loxx*. Snakes {Fitiiopliis iitclanolciiciis and Tluniniopliis clc^^atis) and amphibians [Biifo horcds. llifla re^^illa, ScapJiiojnts Juiinmoiulii, S. intcniiontauus) are found around Mono Lake M\'Z specimens, personal obsenation ), but tliex- are scarce locallx' (personal obsenation). There are no historic records of snakes or amphibians on either island, and x\e .sax\- no ex idence of either during our xisits. .\s discussed abox(^ for lizards, it api)ears that the chance of arrixal and persistence of snakes and amphibi- ans is loxx'. The Mono Fake islands parallel other islands in haxing a greater population al)uiKlance(espe- ciallx Xegit) and a simple species comp(Jsition relatix(^ to the mainland. Larger relatixe abun- dances max be because fexx- predators are pres- ent and tlie lack of nonaxian food competitors, as has !)een postulated for other island rodent populations (e.g., Halpin and Sullixan 1978). The fexx- rodent species, absence of lizards, and 334 Great Basin Naturalist [Volume 52 reduced bird-species richness (Hall et al., in preparation) on the islands may result in density compensation (semn MacArthur et al. 1972, Case 1975) by the islands' Fewmijsais popula- tions. In contrast to island biogeographic theory (Redfield 1976, Sullivan 1977), deer mice are smaller on the islands than on the mainland. Although a founder effect (sen.sti Kilpatrick 1981, Calhoun and Greenbaum 1991) could ha\e resulted in smaller individuals on the islands than on the mainland, there is likely some combination of ecological factors on the Mono Lake islands that has either resulted in maintenance of small body size or has directed selection toward smaller body size. In our study the sex ratio of deer mice appears to be male biased, although more intensive trapping, both within and betsveen years, would be necessan' for confirmation because of potential trapping biases associated with dispersing young males. ACKNO\\'LEDGMENTS We thank Paul Aigner, fean Block, Martin Morton, and Paul Stapp for assistance with fieldwork; Edward Beedy for helping with stud\' design; John Harris and several anonymous ref- erees for reviewing earlier dratts; and Lorraine Merkle for manuscript preparation. Data col- lection was supported by subconsultant contract to Jones and Stokes Associates, consultant to Los Angeles Department of Water and Power and C^alifoniia State Water Resources Control Board; and the White Mountain Research Sta- tion, Uni\ersit\()f California, Los Angeles. Literature Cited BoiKIN D.,\\'. S. BHOKCKKU. L. G. E\F,Kt:TT. J. SlIAPIlU), AND J. A. WiKNS 1988. The future of Mono Lake. University of Califomia, Water Re.source.s Center, Report No. 68. Berkeley, California. 29 pp. BUIK.II. J. B., J. RoiiHINS. AND T. Wainwhiciit 1977. Pages 114-142 in D. W. Winkler, eel. An ecological .study of Mono Lake, California. Unixersih- of Califor- nia, Institute of Ecologx Pnhlication No. 12. Da\is, C^alifoniia. Calhol'n. S. W, and I. F. Chkknbai \i 1991^ Evolution- arv' implications of genetic variation among insular populations of Pcrouujsciis nuinicnlatus and Pcrniiii/s- cus areas. Journal of Mamnialog)' 72: 248-262. Case, T j. 1975. Species numbers, dcnsit\ compensation, and colonizing abilitv of Lizards on islands in the (iulf of California. Ecology- .56: .3-18. . 198.3. Niche overlap and the assemhlv of island lizard communities. Oikos 41: 427—4.33. Fletcher. T. C. 1987. Paiute, pro.spector, pioneer: a his- tow of the Bodie-Mono Lake area in the nineteenth centniY. Artemisia Press, Lee Vining, Ctilifomia. 123 pp. IIaepin. Z. T. and T. P. Sullivan 1978. Social interactions in island populations of the deer mouse, Pcwmy.sai.s maniailatus. Journal of Mammalogv' 59: .39.5-401. Harris. J. H. 1982. Mammals of the Mono Lake-Tioga Pass region. Kutsavi Books, Lee Vining, California. .5.5 pp. . 1984. An experimental analysis of desert rodent foraging ecology. Ecology 65: 1579-1584. jKiii. J. R, JR D.E. Babb. and D. M. Power 1984. Iliston of the California Gull colony at Mono Lake. C^alifomia. Colonial Waterbirds 7: 94-104. . 1988. On the inteipretation of historical data, with reference to the California Gull colony at Mono Lake. CaLifomia. Colonial Waterbirds 11: 322-.327. Kilpatrick. C. W. 1981. Genetic structure of in.sular pop- ulations. Pages 2(8-59 in M. H. Smith luid J. Joule, eds.. Mammalian population genetics. Uni\ersit\- of Georgia Press, Athens. LoEFFLER R. M. 1977. Geology tuid hvdrolog). Pages 6^38 in D. W. Winkler, ed.. An ecological stnd\ of Mono Lake, California. University of California, Institute of Ecologv' Publication No. 12. Davis, California. MacArthur. R. H., and E. O. Wilson. 1967. The theor\- of island biogeography. Princeton Uni\ersit\ Press. Princeton, New Jersey. 20.3 pp. MacArthur. R. IL, J. M. Diamond and ). H. 1v\rr 1972. Densit\' compensation in island launas. Ecolog\' .53: ,3.30^342.' Mono Basin Ecosystem Study Committee. 1987. The Mono Basin ecosystem: effects of changing lake le\el. NatiouiJ Academy Press, Washington, D.C. 272 pp. Pkltonen. a., and I. Hanski 1991. Patterns of island occupancy explained 1)\' colonization and extinction rates in shrews. Ecolog\- 72: 169 suite ol species able to with.stand constantK shifting substrates. Specic^s characteristic ol material greater than 5 cm in diameter (talus) include Hulscci al0(l(i Gra\ and Sciwcio frcDioiitii T &: (i., while Saxifracimens is deposited at the Uni\ersit\ of Idaho IIed)ariuni (ID), with duplicates distributed wid(^l\. Ertters collec- tions are deposited at the Albertson (College of Idaho (CIC). (Collections thought to l)e new records for Idaho were confirmed b\ exjxMts in a particular taxon and/or fiom a search of up to 59 k)cal, regional, and national herbaria ii\Iosele\' 1989). Range-extension data for these s tate- record ta.xa were determined from herbarium records and from the atlases and data bases maintained b\ tli{^ Idaho (>)nsenati()n Data (Center and Mon- tana Natural Heritage Program on the location, distribution, numbers, and condition of rare plant populations in their respectix'c states (Jenkins 19S6). The Ickiho (Consenation Data Center data base was also consulted concerning the current distribution of additional rarc^ spe- cies in Idaho. Results axd Discission The \ascular flora of Kane Lake (Circjue con- sists of 180 species representing 95 genera in 30 families of pteridophxtes, g\nino.sperms. and angiosperms. Of these, 53 species (29%) are ic'stricted to subalpine conununities in the c injue, while 58 species (33%) are re.stricted to al])ine habitats. The remaining 69 species (38%) transcend the subalpine-alpine boundaiA' and occur in both l\ pes of comnumities. Our collec- tions of fi\e species from the stucK area repre- sent their first documented occurrence in Idaho. In addition, four otlier arctic-alpine spe- cies are known from Idaho from ouK a few occurrence's and are considerc-d rare in the state (.\Iosele\ and (inncs 1990). OnK one alien taxon. Taraxacum officiualc Weber was found in tlie stud\ area. Taxa New to Idaho Carex incurviformis Mack. Fhis species occurs in tx\() areas of the North American Cor- dillera: \ar. incuniformis, known from the HockA Mountiiins of British Columbia. Alberta, 338 Great Basin Naturalist [Volume 52 Montana, and now Idalio; and \ar. danaensis (Stacey) Hermann, occurring in the southern Rocky Mountains of Colorado and the Sierra Nevada and White Mountains of California (J. Mastrogiuseppe, Washington State Universitv; personal connnunication, 1991). The popula- tion in Kane Creek is disjunct south from the next closest knowii population in Deer Lodge Count\-, Montana, b\' about 260 km {Lack- scliew'itz 393S MONTU; Lesica and Shelly 1991). We found one small population in the Kane Lake Cirque, occurring in a steeply slop- ing meadow on seepy ledges at 3350 m at the southern end of the cinjue. Draba fladnizensis Wilfen. A widespread circmnpolar species, Draba fladnizensis is sparselv distributed in North America, from the arctic south through the Rock-v Mountains to Utah and Colorado (Hitchcock 1941). As withC<7/Y'.v incitniforniis, the Kane Lake Cirque population is disjunct south from the next ck)s- est known population in the Storm Lake area of the Pintlar Range, Deer Lodge Counts', Mon- tana, bv about 260 km [Lackschewitz 6120 MONTU). Several verv small populations occur on ledges and in rocky areas south of Kane Lake, including sprav zones of waterfalls, bare stream gravels, and on steep, rock^' slopes near seeps. Potentilla nivea L. This circumpolar spe- cies occurs in arctic and alpine regions of North America, being pre\iousl\' knowai in western North America from Alaska south along the mmn crest of the Rock-\' Mountains to Montana, Wyoming, Colorado, and Utah and east to Nevada (Hitchcock and Cronquist 1973). The Kane Lake Cirque population is disjunct from the nearest Montana populations by perhaps 280 km. A small population of about a dozen [)lants was seen in a moist, sloping meadow at the top ()( the waterfalls south of Kane Lake at 2950 m. Ranunculus gelidus Kar. & Kir. A North American endemic, this species is distributctl across the arctic, southward in the Rock\ Moun- tains to Colorado (Benson 1 948). The very small population in Kane Creek Cirque represents a disjunction southwestward of about 350 m froui the Beartooth Plateau, Stillwater Countw Mon- tana {Stickney 4 MRC; Lesica and Shellv 1991 ). In the study area it occurs in a stringer of Deschanipsia cespitosa along the northeastern tributaPy- of Kane Lake at about 3170 m. Ranunculus pygmaeus Wahlenb. This buttercup is circumpolar, occurring south along the Rock-x- Mountain crest to Colorado (Benson 1948). Its presence in the Kane Lake Cirque represents a disjunction of about 200 km south- west from the next nearest known populations in the Pioneer Mountains, Beaverhead Countv, Montana (Hitchcock and Midilick 12899 WS'). Raniincidus pi/(iniacus is relati\el\- connnon in the Kane Lake Cirque, occurring in moist, exposed soil along creeks, on ledges and slopes, and occasionally in cracks in cliffs. Additional Rare Species Erigeron humilis Grahm. This circmnpo- lar species was not known from Idaho until Henderson et al. (1981) reported it from the Lemhi and Lost Ri\er ranges. Eight occur- rences are now knowii from the state, with the Kane Lake Cirque populations being the only ones known outside the two ranges mentioned above (unpublished data on file at the Idaho Conseivation Data Center, Boise). Erigeron liuniilis is relatixeh' common in moist Dcscliainpsia cespitosa meadows throughout the lower portion of the cirque. Paruassia kotzebuei Cham. This species was also not knowni from Idaho until recently when Brunsfeld et al. (1983) reported it from the Lost River Range and Pioneer Mountains. Foui- occurrences are now^ known from the state (unpublished data on file at the Idaho Conser- \ation Data Center, Boise). It is relativelv common on moist ledges and in sloping Descliampsia cespitosa meadows throughout the lower portion of the circjue. Saxifraga adscendens L. The North Amer- ican representatixe of this wide-ranging species, \ar orcf^onoisis (Raf.) Breit., occurs throughout the RockA Mountains and northern Cascade Range (Hitchcock and Cronquist 1973). In lelaho it is known from nine sites in the White ('loud Peaks, Pioneer Mountains, and Lost \\\\vr Range (unpublished data on file at the klaho (]onsenation Data Center, Boise). Kane Lake (>ir(jue populations occur throughout the area on moist scree, sand, and graxel. often along streams. Saxifraga cernua L. Se\en small popula- tions of this circumboreal species are known from Idaho (unpublished data on file at the klaho Consenation Data Center, Boise). At Kane Lake (>irque it is wideK' scattered in small [)ojiulations from moist subalpine ledges north of Kane Lake at 2S00 m to ledges and cracks on the headwall at 3400 in. 19921 Kane Lake Cikole \'asli l.\k Flora 339 Annotated Checklist of Vascular Plants The checklist is arranged b\ dixisioii and class (in Magnohoph\ta), then alphaheticalK h\ hmiiK; genus, and species within these major groupings. Nomenclature generalK follows Hitchcock and Cronquist (1973), exceptions heing Salix (Bnmsfeld and |ohnson 1985), Carex incuniformis and C. sco})iil()rum \ar. hracteosa (Hermann 1970), antl Enoiiuiii (■(ipisfrafii))i (Re\eal 1989). Unless othen\ise noted, th(^ collection numbers are the authors". Di\ isiON Lvcopodkm'uvta Srlasjiiirllaceac" Selaginella densa Rvdb. Conuiion in suhalpinc and alpine zones; moist to ili"\ slopes antl leclws and bonlder fields. 1177, 2319, 2.343. Artemisia michauxiana Bess. Uncommon in moist, unstable, rock'^• drainage bottoms; snbalpine and lower alpine zones. 2.363. Artemisia tridentata Nutt. Rare on dr\ snbalpine slopes north ol Kane i^ake. 2261. Aster alpigenus (T. & G.) Gray var. haydenii (Porter) Cronq. Di-\- op'-nings in forest north of Kane Lake. 2419. Aster foliaceus Lindl. var. apricus Gray. (Connnon in moist alpini' meadows east ol Kane Lake. 1175. Aster stenomeres Grav. Dn, rock)' ledges in forest openings nortli of Kane L;ike. 22.35. Chaenactis alpina (Gray) Jones. Uncommon in snb- alpine and alpine d?\. saiuK scree. 2.361. Cirsium tweedyi (Rvdb.) Petr. (Connnon in moist meadows and on ledges in idpine zone. 2.37S. Erigeron acris L. var. debilis Gray. Connnon in moist, sand\' soil; snbalpine and aljMne zones. 11S.3, 22S7. 2.344. Erigeron asperuginus (Eat.) Grav. Dv\ slopes and ledges; common in snb;ilpine and nnconnnon in lower alpine zones. 22.50. 2.350. Erigeron compositus Pursh \av. glabratns Macoun. ("omnion on tin snbalpine antl alpine letl^es. 22(')5. Erigeron coulteri Porter. Rare in alpine meatk)ws along creek east ol Kane Lake. 1 174. Erigeron humilis Graham. L>ocall\ connnon in moist ;il|)ine meadows. 2274. 24 10: C.iicco 2S-1, Erigeron percgrinus (Pursh) Cireene ssp. calliunthemtis (Greene) Cronq. \ ar. scaposus (T. & G.) Cronq. Connnon in moist to wet snbalpine meadows aronntl Kane Lake. 2.306. 2.367. Erigeron simplex Greene. C^ommon in snbalpine and al[inie zones; moist meatlows anil slopes. IISS. 2270. 2.3.38; Caicco 476: I'a-tter 21()S, Haplopappus Itfallii Gra\. Unconnnon oti dn alpine letlues. 2402. Haplopappus macronema (iray. Unconnnon on dr\ subalpine knoll, within forest Tiorth of Kane Liike. Not collectetl. Haplopappus suffruticosus (Nutt.) Gray. Uncom- mon on (lr\ sub;ilpine knoll, within forest nortli ol KiUie L;ike. Not collected. Ilieracium gracile Hook. Uncommon in dn forest openint^s north ol Kane Lake. 2.30.5. llulsea algida Gray. Common in alpine t;ilns. 2403. Microseris nutans (Geyer) Shultz-Bip. Uncommon in snbalpine meadows north ol Kane L;ike. 2.3S5. Senecio cymbalarioides Buek. Connnon in moist sub- alpine and alpine me;ido\ss. ! 17.3. Senecio fremontii T. & G. var./rp»io»i/ii. Common in alpine talus. 24(K). Senecio streptanthifolius Greene. Common in sub- alpine zone; dn slopes and Itjrest understor)'. 22.55. 340 Great Basin Naturalist [Volume 52 Solida^o multiracUata .\it. \ar. scoptilorum Gray. DiT. roc'k\' siihalpiiic and alpiiu' Icdiies. 225S. Taraxacum lyrutum (Ledeb.) DC. (^omiiion in alpine zone; moist meadows and slopes. I 185, 22(S9. Taraxacum officinale Weber. Alien: rare in snhalpine meadows north of Kane Lake. 23S(S. Hora and nnidentifiable to species. Uncommon in dn to moist forest openings north of Kane Lake. 2375. Arabis lemmonii Wats. var. lemmonii. (Common on (h-v. mistahle iiipiiie slopes. 2313. 2356. Arabia microphylla Nutt. ^ar. microphyUa. Connnon on su!)alpine ledges and slopes north ol Kane Lake. 224S. Arabis microphyUa Nutt. \ar. saximontana Rollins. Uncommon in moist soil of alpine zone. 2374. Draba sp. Unable to identifv; possibK' a new taxon. Rare; .seen onl\- in one small, steepK' sloping, moist meadow at 3353 m. east ol Kane lake. 2412. Draba fladnizensis Wilfen. ("ircnmpolar: rare on tlis- tnri)ed, bare-soil microsites of steep alpine slopes and along rivulets. 1 107. Draba lonchocarf)a Rydb. var. lonchocarpa. Clonmion througliont cinjue on moist ledges and slopes; alpine zone. 1 lOtS. 2:U4; Lrtter 2106. Draba oligosperma Hook. var. oligosperma. Haic on di"\ alpine slopes and letlges. 2357, 2362; Ertter 2102. Draba paysonii Macbr. var. treleasii (Schulz) Hitchc. Unconnnon in dr\. sand\ alpine soil. 2405. Erysimum asperum (Nutt.) DC. Rai"e in dn' subalpine tains noi'tli ol Kane Lake. 2377. Smelowskia cahjcina (Steph.) C.A. Mey. var. amer- icana (Rej^el & Herd) Drurv & Rollins. Unconnnon on dn', exposed alpine slopes 2340; Ertter 2107. (Janoplnllaceae Arenaria aculeata Wats. Dw. sandv slopes; connnon in subalpine and rare in alpine zone. 2236, 2351. Arenaria congesta Nutt. I'ncornmon on dn alpine- slopes east of Kane Lake. 1 1S7. Arenaria obtusiloba (Rydb) Fern. Dn, exposed slopes and ledges; connnon in alpine and uni'ommon in suba!pin<' zone. 2354. Arenaria rubella (Wahlenb.) J.E. Smith, ('ir- cnuiboreal; nncouunon on moist to dr\ alpine ledges. 2424. Cerastium berringianum C^iain. & .Schlechl. (lonmiou in alpine zone throughout cinjue; moist slopes, meadows, and Ii'dges. 2321, 2413. Sagina saginoides (L.) Britt. C>'ircnmborial: uncom- mon in moist al|)ine uu^adows. I 179, 2260. Silene douglasii Hook. var. douglasii. i)r\, rot k\ ledges; uncommoTi in subalpine and lower aliiine zone. 2364. Silene repens Pers. var. australe Hitchc. & Maj^. Rare among rocks ol'boulder field east of Kane I .ake. ( laicco 2S6. Stellaria longipes Goldic \ar. altocauUs (Hulten) Hitchc. Uncommon in moist, sandv sites and scree in alpine meadows. 1180,2327. Stellaria umbellata Turcz. Rare in wet to moist grawls along alpine rivulets. 2326, 2347. ("rassnlaceae Sedum lanceolatum Torr. \ar. lanceolatum. (iommon on moist to df\ snl)al[iinc and alpine slopt^s and ledges. 2240. Ericaceae Kalmia microphylla (Hook.) Heller, ('onunon in moist to wt't sub;ilpine ;md alpine meadows. 2304. Ledum glandulosum Nutt. var. glandulosum. (Common in moist subalpine^ forest and meadows around Kane Lake. 2303. Phyllodoce empetriformis (Sw.) D. Don. (Connnon on moist s\ibalpine and alpini' slopi's. 2300. Phyllodoce glandulifera (Hook.) Co\. Common on moist subalpine and alpine slopes. 2302. \Phyllodoce intermedia (Hook.) (Jamp. ( .'ommon on moist subalpine and alpine slopes. 2301. Vaccinium scoparium Leiberg. (Jonunon in dn sites in un(lerstor\ of forest and knnnmholz. 2237. Fabaccnie Astragalus alpinus L. ('ircumboreal. ('ommon in moist meadows diroughont cir(|ue; subalpine and alpine zones. 2318. 2373; C^aicco 474. Astragalus eucosmus Robins. Rare in cracks of moist cliff u("ar stream; alpine zone. 2396. Astragalus kentrophyta Gra'v var. implexus (Canby) Baniebv. Common on exposed, dn' alpine slopes and letlges. 2352; Ertter 2102. Trifolium longipes Nutt. var. pedunculatum (Rydb.) Hitchc. I'ncommon in deep soil alf)ng subalpine strcambank north ot Kane Lake. 2380. Gentianaceae Frasera speciosa Dougl. Uncoiumon in dr\ subalpine talus north of Kane Lake. 2415. Gentiana calycosa Griseb. \'ar. asepala (Maguire) Hitchc. (Connnon in moist subalpine and low alpine iriead- ows. 1172. Gentiana prostrata Haenke. Rare; seen onl\ in moist, steepK' sloping meadow above ponds t'ast of Kane Lake; ;ilpine zone. 240S. (ii'ossnlariaceae Ribes ceniitum Dougl. var. inebrians (Lindl.) Hitchc. Uncommon in subalpine and alpine zones; dw h'dges and boulder fields. 2400. Ribes hendersonii Hitchc. Rare anil local in dr\ boul- der field (.'ast of K;me L;ike; alpine zone. 2416. Ribes lacustre (Pers.) Poir. L'ncommon along snb- ;ilpine creek near outlet of Kani' Lake. 2398. Ribes montigenum McClatchie. Common in boulder fields and dv\ forest nud(-rstor\; subalpine zone. 2310. i hdrojiliv llaceae Phacelia hastata Dougl. \ar. alpina (Rydb.) Cronq. Unconnnon in moist to dr\ alpine tains. 2406. Ouagraceae Epilobium alpinum L. var. alpinum. Conmiou on moist, unstable subalpine- ;iud alpine slopi-s; eircnmboi"i-al. 23:5;5. Epilobium angustifolium L. Rare in i.\y\ forest open- ing nortli ol K;me Lake. 2418. Epilobium glaberrimum Barbey var. fastigiatum 1992] Kaxk Laki-; CiHyiiE VAScuLy^ fYoiu 341 (Nutt.) Trel. Uncoiiinion in moist meadow al()iitrate. Fn- originating from eggs near the falls could be lost through passixe drift if thev became free-sxximming at night and xxere consequentlx displaced doxxnstream in the darkness, as has been described of European graxling (7' tiiyinallus; Bardonnet and Gaudin 1990). Doxxnstream losses could also represent passive drift of dead or vmhealthx' fish, as sug- ge.sted by a report that 819f of xoung broxxn trout produced in a section of stream did not surxixe and drifted downstream, mostly at night (Elliott 1986). We did not attempt to determine the health of xoung graxling in the falls trap. Loss oxer the falls could be an indirect con- sequence of local dispersal of young xvithin the stream as thex' became free-.sxximming. Young sockexe salmon {OncoHit/ncliiis iicrka) ol outlet-spaxxning populations liaxe been reported to temporarilx disperse doxxnstream before holding position or sxximming upstream into lakes (McCart 1967, Brannon 1972). Younu graxling in Deer Dreek iilso disperse localK from th(^ immediate spaxxiiing areas, some of them apparentlx' doxxnstream. For tho.se becoming free-sxximming near the falls, exen localized doxxnstream dispersal coukl result in some being carried oxer, especiallx under con- ditions of poor xisibilitx' at night. The results indicate that Deer Lake grax ling spend at least the first, and possibly also their second, sunnnerand earlx' to mid-autunm in tlie outlet stream, lloxxever, the results ditl not permit us to determine the exact timing of most moxement by young into the lake, or xx'hether they move upstream predominantlx' as age-0 or as age-1 fish. The x-ery fexv xoung that moxed into the lake during both obsenation seasons coidd not account for the numbers of spaxxning adults produced in the population. Since there is no other source of xoung, and since the 1989 obserxation season extended oxer the entire ice- free period on the stream, maintenance of the Deer Lake pojiuiation must depend on upstream moxement of xoung .sometime during the six to sexen months of annual ice coxer. Althouo;h age-O xoung greatlv diminished in numbers and age-1 fish xirtuallx' disappeared from the stream betxxeen the on.set of ice coxer in Nox ember 1989anditsthax\ingin fune 1990. xxe do not knoxv the proportions ol these reduc- tions in numbers attributable to moxement into the lake, death, or loss oxer the falls. The greatlx' diminished numbers of xoung in the falls trap during late sununer and their absence in the trap bx October of both xears suggest that doxxn- stream losses during winter max' be small. The chronologx of major moxement bx xoung grax- ling into the lake and the numbers and ages of fish inxolxed xxould need to be resoKod bx obserx ations during xxinter. Little is knoxxn about duration ol stream residence lor outlet-spaxxniing populations ol .\rctic- grax ling. Younglrom inlet-spaxxning pop- ulations of the .species txpicallx- haxe an early descent to the lake, ranging from immediately after sxximup (Knise 1959, Lund 1974, Wells 1976) to xxithin .sexeral xxeeks (Nelson 1954). We are not axxare of other studies on stream residence times of voung grax ling from outlet- spaxx'uing populations and so do not knoxx' w hether extended period of stream residence is txpical for such populations. Young rainboxx' trout of outlet-,spax\ning populations tend to remain for extended periods of at least a month to a xear or more before migrating upstream to lakes, xx'hile those of inlet-spaxxning populations 350 Great Basin Naturalist [Volume 52 mio;rate when newlv swimiuing in some popula- tions and after extended periods of stream resi- dence in others (Northcote 1969). The extended stream residence of voung Deer Lake grayling is also consistent with their lesser ten- dencv to swim upstream in an artificial stream as early fiy (from swimup to three weeks), com- pared with their responses when older, within a study period of up to 10 weeks post-swimup (Kayal989, 1991). It may be that young of an outlet-spawning population need to attain larger sizes and thereby become stronger swimmers before they can swim upstream into the lake. However, this possibilit)' appears contradicted by oiu" casual obsei-vations that age-0 grayling of all sizes in Deer Creek, starting from those newly swim- ming, were capable of swimming upstream when they w^ere disturbed by our presence. Those young originating from spawaiing areas within a few meters of the lake outlet could ha\e entered the lake by mo\ing onl\' a short distance upstream. Another possible factor, (jualitv of rearing habitat, also does not appear to favor extended residence in Deer Creek. Deer Lake grayling grow slower during their first two years than those of other lacustrine populations studied thus far in Montana, but thereafter they grow at similar or faster rates (Deleray 1991). Unlike yovmg Deer Lake grayling, those from inlet- spawning populations in Montana spend their first summer and autumn growing season in lakes. The slower early growth of Deer Lake gra)'ling thus appears related to their spending their first growing seasons in the stream rather than in the lake. We speculate that young Deer Lake grayling may remain in the outlet stream to avoid intra- specific predation in the lake. Eriksen (1975) obsen'etl that age-0 grayhng in several Montana lakes occupied shallow, near-shore areas among rooted aquatic vegetation, and suggested that their distribution pro\ided protection against predation by the adults. Behavior of the few post-spawning adults that remained in Deer Creek during the suuuner of 1990 confirmed that adults will prey on the voung. Young gray- ling would likely be susceptible to predation by larger conspecifics in Deer Lake because of its high water clarity- throughout the summer and the lack of rooted macrophvtes. In the outlet stream the only potential predators of x'oung gra\ling that we saw were the relatively few residual adult and age-1 grayling remaining through the summer, and an occasional belted kingfisher (Axes, Ccnjlc alci/oii). Thus, the movements of age-0 Deer Lake grayling that remain in the outlet stream appear adapted both to beginning their existence a short distance aboxe a waterfall and to a\oidance of predation b\- larger conspecifics in the lake. Acknowledgments These observations were part of a stud)- sup- ported by a grant from the Montana Depart- ment of Fish, Wildlife and Parks. Literature Cited Rakdonnet. a., and R Galdin, 1990. Diel pattern of first dowii.stream post-emergence displacement in grayling, Thi/iudllu.s thyinalhis (L. 1758). Journal of Fish Biologv- 37:62.3-627. Brannon. E. L. 1972. Mechanisms controlling migration of sockexe salmon fW. International Pacific Salmon Fish- eries C]ommission, Bulletin 21. 86 pp. Giiai>ma\. D. W., and B. M.\\. 1986. Dowaistream move- ment of rainbow trout ptLst Kootenai Falls, Montana. North American |()urnal of Fisheries Management 6: 47^51, Deleray. M. A. 1991. Movements and utilization of fluvial habitat by age-0 Arctic grayling, and characteristics of spawning adults in die outlet of Deer Lake, GaUatin County, Montana. Unpublished masters thesis, Mon- tana State Universitv, Bozenian. 7.5 pp. ELL,i(yrT. J. M. 1986. Spatial distribution and beha\ioural movements of migratoiv trout, Saliiio tnitta, in a lake district stream. Journal of Animal Ecology 55: 907-922. Eriksen. C. H. 1975. Physiologic^ ecolog\- and manage- ment of the rare ".southern" grayling, ThijinaUus arcti- ciis tricolor Cope. Internationale Vereinigung fiir Tliet)retische und Angewandte Limnologie 19: 2448- 2455. Fkalev, J. J., M. A. Galb and J. R. Ca\ ic;li 1986. Emer- gence trap ;uid holding bottle tor the capture of salmo- nid fnin streams. North Americiui journal of Fisheries Mmiagement 6: 119-121. IIKNSIIALL. J. A. 1906. Culture of the Montana grayling. Report of the Conmiissioner of Fisheries for the Fiscal Year 1906 ;uid Speci;il Papers. U.S. Bureau of Fisher- iis. Document 628, Washington, D.C. 7 pp. |()NSS()\ B. 1982. Diadromous and resident trout Stiliiw tnttta: is their ditic'rcncc due to genetics? Oikos 38: 297-300, Kay\ (]. M. 1989. Rheotaxis of voung Arctic gravling from populations that spawai in inlet or outlet streams of a lake. Transactions of the American Fisheries Socieb.- 118:474-481. . 1990. Status report on fluvial Arctic gravling (Tliy- Diallu.s (irctiai.s) in Montana. Prepared for Montana Department of Fish, Wildlife luid Parks, Helena. 97pp. . 1991. Rheotactic differentiation between fluvial and lacustrine populations of Arctic grayling (Thy- in/illu.s iirctictis), and implications for the only remain- ing indigenous population of fluvial "Montana 19921 Stream Mu\ kmknts of A(;k-o Lakk c;iuvli\g 351 grayling." Canadian Jonrnal of Fislieries antl \(|natif Sciences 48: 5.3-59. " kiaiSE. T. E. 1959. Grayling ot (Jrehe Eakc, '^Vllow stone Nationiil Park, Wyoming. U.S. Fish iuicl W'ildlilc Ser- vice Fisheiy Bulletin 149: 307-.351. Fkni'm II. L. D. 1985. EN'aluation of xoiing-ot-tlie-xcar production in a unique Colorado wild trout population. Unpublished masters thesis, Colorado State Unixcr- sit\'. Fort Collins. Land. J. A. 1974. Reproduction ol salnionids in tlie inlets of Elk Lake, Montana. Unpublisheil master's thesis, Montana State Unix ersitw Bozeman. .\k,C,\HT. P. 1967. Behaviour and ecology of sockexesiilmon frv in the Babine Ri\er. Journid of the Fisheries Research Board of C;uiada 24: 375-428. Nelson, P. H. 1954. Life histoiv luid management of the American grayling {Tluimallus siginfer tricolor) in Montana. Journal of Wildlife Management IS: 325- 342. NORTIICOTE. T. G. 1962. Migratorv- behaviour of juvenile rainbow trout, Salmo oairdncri, in outlet and inlet streams of Loon Lake, British Columbia. Joum;il of the Fisheries Research Board of Canada 19: 201-270. . 1969. Patterns and mechanisms in the lakeward migraton' behayiour of juvenile trout. Pages 18.'3-203 in T. G. Nortlicote, ed.. Symposium on salmon and trout in streams. University of British Columbia, \';ui- conver, B.C., Cimada. . 1981. Juvenile current response, growth iuid matu- ritv of abo\e luid belovy stocks of rainbow trout, Salino gairdneri. Joumal of Fish Biolog>' 18: 741-751. XoinilcoTE, T. G., AND G. F. H.\irrM..\N. 1988. The biology and sigTiificance of .stream trout populations (Salmo spp.) living above and below waterfalls, l^olskie -Xrehiwum i Ivdrobiologii .35:409—442. NoHTiicoTK, T C. wn B. W. Kei.so 1981. Differential response to water current by two homozxgous LDIl phenotvpes of voung rainbow trout. Canadian Journal ol Fisheries and .\quatic Sciences .38: .348->3.52. I'iri'H R. G., 1. B. Mc:Ee\\ai\, L. E. Oh.me, J. P McCkahen, L. G. Fow'i.EK, AND J. R. Leonakd. 1982. Fish hatchery management. U.S. Department of the Interior, Fish and Wildlife Service, Washington, DC. 517 pp. S( i;i\ I \KH. J. C, AND M. J. Bkowni.kk 1989. Effects of forest harvesting on spawning gravel ;uitl incubation suiAival of chum {Oncorhijucfiits kettt) iuid coho salmon [O. kistifcli) in Carnation Creek, British Colimibia. C'anadian Journal of Fisheries and Acjuatic Sciences 46: 681-696. \'i\c:E\T, R. E. 1962. Biogeographical and ecological factors i-ontributing to the decline of Arctic gravling, Thy- iiuilUis arctints Pallas, in Michigan and Mont;uia. Unpublished doctoral dissertation, Universitv ol -Mich- igan, Ann .^rbor. Wells, J. D. 1976. The fishen of Hyalite Resenoir during 1974 and 1975. Unpublished master's thesis, Montana State Universitv, Bo/eman. 47 jip. Received 7 May 1991 Accepted 15 August 1992 Givat Basin Naturalist 52(4). pp. 352-356 EFFECTS OF BROWSING BY MULE DEER ON TREE GROWTH AND FRUIT PRODUCTION IN JUVENILE ORCHARDS Dennis D. AiLstin and Philip J. Unless Abstiuct. — The effects of big game depredation on jnvenile fruit trees were studied in northern Utah. Utilization of trees was determined by counts of nipped tuid intact buds in spring. Heiglit, width, l)asal diameter, number of l:)uds, and initial fruit production of peach and apple trees were determined from trees protected from or bi'owsed b\' mule deer in winter. Results from the 10 orchards studied indicated that remov;il of buds at the observed browsing levels had no effect on tree growth or initial truit jirotluction. brow.' Ki'i) tLortls: (Icprcchitiou. mule deer, orrluirds. fruit trcc\. deer dtiina^c crdluiitinii. 1 cm in length (Austin and Umess 1987). Protnided was defined by visualizing a perpendicular line from the twig to the tip of the bud, and an obsenable space was re(juired between the line and the bud-twig intersection. Tree growth measurements were taken after Department ol'Raiiile Seience, Utali State Univer.si(\ , Lxigaii, Utali 84:322-.523(). 352 19921 Dekh Bhowsinc; in |r\ iaii.i: Okcii ahds 353 tlie end of the growing season ImU before winter browsing occurred. Tree height was measured to tlie nearest 1.0 em from ground le\('l. tree width to (he nearest 1.0 cm at the height where maximum width occnn-(nh Width was measured in north-south and east-west directions and the mean recorded. Basal trunk diameter was mea- sured to the nearest 0. 1 cm using dial calipers at 10 cm ah()\e the graft scion. Diameter was sim- ilarh measiu-ed on north-south and east-west directions antl the mean recorded. The number of intact buds, using tlie same definition as tliat for bud-remo\al determinations, was counted using hand-tall\' registers. W'liere hanestable crops were produced, all fniits were hand- picked and counted. Specific methods are reported in the results for each orchard. Data were anal\"zed between prottx'ted and browsed trees and bet\\'een trees with \arious intensities of browsing, using the standard t test of the means. Confidence lexel was .set at P < .05. Results Orchard 1 A 4 X 6 block of 24 ec^ual age and size Elberta peach trees, planted in spring 1986, was selected for study. Alternating trees, deter- mined b\ coin toss, were fenced during three winters, 1986-89. During the fourth winter, 1989-90, all trees were fenced. Because within- vear browsing effects decrease fniit production (Katsnia and Rusch 1980, Austin and Umess 1989), trees were protected from browsing to compare production between prexionsK browsed and protected trees. Tree measuic- inents were taken, and peaches were hand- picked and counted in late summer 1990, the lirst year of commercial harvest. Percent bud remoxal as measured in spring 1987, 1988, and 1989 was 35.6, 76.6 and 73.57^. respectively. Even with (his high degree of brow.sing by deer, trees fulK recoxcred during (lie summer groxxing seasons. No differences between protected and browsed trees were found for anx- tree measurements or fruit pro- duction (Table 1 ). Orchard 2 A small commercial orchard comprising 210 Elberta peach trees x\as planted in spring 1986. Percent oxenxinter bud remoxal xvas deter- mined in earlx- spring 1987. Since 9 trees shox\ed bark scraping damage, they xxere deleted from the sample. Trees were placed into three ecjnal groups of 67 bx' the percentage of bud-remoxal browsing damage: heaxy 61- 100%, moderate 34-60%, and light 0-33%. Tree measurements xvere made folloxxing the 1987 summer growing period. No differences in tree measurementsxx'ere found aniongthe three intensities of browsing bx mule decM^ (Table 1). Orchaicl 3 TweKc [xuvs of ecjual age and size Yellow I^elicious aj)ple tr(H\s w(m'(^ carefully .selected bx' ( )ci 1 lar ( )1 )seiA at ion wi( hi 1 1 a commercial orchard planted during spring 1984. One tree of each pair, determined bx coin toss, xx'as protected liom broxvsing bx' fencing dming fixe xxinters, 1984-89. During the .sixth winter. 19S9-90. for tlu^ same reason as described for orchard 1. all trees were fenced. Percent bud remoxal from browsing was 76.4, 60.5, 41.7. 23.6. and 63.2% foryears 198.5- 89, respectixelx'. No differences betxx'een pro- tected and broxvsed trees were found for anx' tree measurements or I ruit production Table 1) Orchard 4 Twelxe pairs of equal age and size Red Deli- cious apple trees xx'ere carefullx' selected b\ ocular ob.seiA ation xxithin a connnercial orchard planted in spring 1983. One tree of each pair, determiiu^d b\ coin toss. x\as protected from broxvsing bx fencing during three x\inters, 1984-87. During winter 1986-87 a deer-proof fence xvas constructed around the orchard, and, cf)ns(H|uentlx, deer use was close to zero (0.4% ). During the txx'o prexious winters (1984—86) per- cent bud remoxal xx'as 71.0 and 17.0%, respec- ti\(4x. No differences between protected and browsed trees xxere found for either tree niea- surcMuents or number of fruits (Table 1). Also, flow(>r cluster counts. x\hich were collected in spring 1987 as part of an ongoing jiarallel stud\- (Austin and Unless 1987), showed no difference between protected (x = 166) and broxxsed (x = 169) trees. Orchard 5 Txx'elxe pairs of equal age and size Red Deli- cious apple trees xx'ere selected xxithin a com- mercial orchard planted in spring 1985. One tree of each pair, determined bx' coin toss, x\as protected from broxxsing during four xxinters, 1985-1989. During the fifth winter. 1989-90, all trees xx^ere fenced. 354 Great Basin Naturalist [Volume 52 Table 1. Mean growth incasurement.s and initial fruit production from juvenile peach and apple trees protected from or browsed bv mule deer in winter Mean tree measurements Orcluird No. Fruit tree Treatment Years Basal % buds Height Width diameter No. of No. of removed (cm) (cm) (mm) buds fniits 1 Elberta peach Browsed 12 1986-90 62 225 257 5.6 104 Protected 12 230 247 5.7 — 103 2 Elberta peach Hea\il\ browsed 67 1986^87 61-100 120 88 2.6 61 — Mfxlerately browsed 67 34-60 124 92 2.7 67 — Lightly browsed 67 0-33 122 91 2.7 65 — 3 Yellow Delicious Browsed 12 1984-90 53 192 1.36 5.1 250 72 apple Protected 12 193 149 5.2 238 70 4 Red Delicious Browsed 12 1984-87 44 569 248 4.4 .349 75 apple Protected 12 588 262 4.4 375 59 5 Red Delicious Browsed 12 1985-90 24 259 163 5.4 .577 3 apple Protected 12 250 158 5.4 570 3 6 Golden Delicous Heaxily apple browsed Moderatelv 20 1987 6.5-92 198'' 9:1' 3.5 96 — browsed 20 2<8-64 192'' 88 3.5 93 — Lightly browsed 20 0-27 175'' 8& 3.5 92 — 7 Red Delicious Hea\ily apple browsed Moderatelv 8 1985-.S6 49 88 22 1.7 11 — browsed S 21 98 30 1.8 10 — Protected 8 92 21 1.6 " — 8 Mcintosh apple Hea\ily browsed 8 1985^86 50 132 62 2.4 31 — Moderately browsed 8 35 126 47 2.1 22 — Protected 8 129 44 2.6 17 — 9 Jonathan apple Ileavilv browsed 8 1985-^86 28 147 69 2.4 26 — Moderatelv browsed 8 22 123 48 2.0 22 — Protected 8 131 69 2.0 45 — 10 Red Delicious Browsed 12 1985-87 39.4 167 67 5.1 90 apple Protected 12 159 63 5.0 107 — ' 'F"igiires with tltffcrt'iit .supi.Tscriptfii nnnihi-rs uitliiii tolii vere .signiHcaTitK (lilferent, P < .0.5. Percent bud renunal hoiu browsing was Orcliard 6 16.7, ().(), 16.7, and 61.0 for years 1985-89, respecti\-ely. No differences behveen protected A 2 x .30 block of 60 two-year-old Golden and browsed trees were found for any tree mea- Delicious apple trees was measured for over- surenients or fmit production, which was winter bud-reni()\al browsing use in spring greatly reduced in 1990 dut^ to cold temptMa- 1987. Utilization during the pre\ious winter was tures in spring (Table 1). unknowai, but was probably similar to the use 1992] Dkkh Hi^()\\si\(; i\ ji \ kmlk Ohcilvj^ds 355 ineasunHl in 1987. Percent lnul renunal ranged from 0 to 927f . with a mean of 46.79f (Table 1 ). Trees were plactnl into three groups of 20 hv l)ud-renio\-al classes: 0-27, 28-64, and 64-929f . SinprisingK", heaxilv and moderateK' browsed trees had significanth' greater height at the end of the growing season than lightK browsed trees, and hea\il\ browsed trees also had greater width than lightK' browsed trees (Table 1). Although other factors, such as pRuiing, could ha\e accounted for these increases, height and width ma\ ha\e been increased b\ browsing. No differences were found in basal diameters oi- number of buds. Orchards 7. S. 9 Twentv-four ecjual age and size trees of Red Delicious, Mcintosh, and Jonathan apples were planted in spring 1985 for this stud\'. In winter 1985-86, one-third (8 of each species) of the trees, randoniK' selected, were protected; one- third receixed moderate browsing by tame mule deer as modified by temporary fencing; and one-third recei\ed hea\A' browsing. Mean bud remo\al \aried from 21 to 35% under moderate browsing, and 28 to 50% under heavy browsing (Table 1). Following the summer growing season in 1986, no significant srowth differ- ed o ences in tree measurements were found betx\een protected, moderately browsed, or hea\il\ browsed trees (Table 1). Orchard 10 TweKe pairs of equal age and size Red Deli- cious apple trees were selected within a com- mercial orchard planted in spring 1983. One tree of each pair, determined b\- coin toss, was protected from browsing during winters 1985- 87. Percent bud removal from browsing was 76.6, 37.4, and 4.1%, respectixelw No differ- ences between protected and browsed trees were found (Table 1). Discussion Percentages of bud remcnal measured Irom these 10 orchards were mostk' less than 65%. Browsing by mule deer during winter dormancv' at this level of use was not sufficient to cau.se a decrease in tree growth parameters measured. From the view of carboh\drate resenes, decreased producti\it\ would not be expected if the total number of^ intact buds axailable for spring growth were sufficient to maintain balance with the root swstem. This was the obsened case. In this stiuK trees were not browsed sexerely. As a suggestcnl dehnition, severely browsed trees would include browsing of >90% of the axailable protruded buds, removal of >70% of the current animal growth, scraped bark on the central leader and/or scraped bark- on two or more priman- branches, or limb breakage. C-'eitaiuK, as the level of browsing increases toward severe levels, the potential for permanent daiuage and reduced growth also increases. The level of l)r()wsing intensitv' needed to damage juxenile fruit trees is unknowii, but it is apparenth higher than that w hich occurs in most depreciation situations in northern Utah and elsewhere (Harder 1970, McAninch et al. 1985). The intensitv of browsing needed to cause measurable damage would also be expected to \"an- with the qualitv* of the horticultural prac- tices inx'olved in managing the orchard. In this stud\ all orchards received high-intensit\' care, including adequate irrigation, periodic spra\- ing, weed control, etc. Orchard trees receixing lower intensities of care and increased emiron- mental stress from pests, or competition from weeds, may respond negativelv to similar levels of deer browsing. In conclusion, the results from this stud\ of juvenile apple and peach fruit trees were con- sistent with pre\ious research (Harder 1970, McAninch et al. 1985). Browsing bv mule deer at the intensities observed had no negatixe effects on tree height, width, basal diameter, number of buds, or initial fruit production. ACk'XOWLF.nCMF.XTS This report is a contribution ot the Itali State Dixision of Wildlife R(\s{)urces, Federal Aid Project \V-105-R. Liti:k.\tl'hk Citkd .'Vl sri\ I). D.. AM) P. J. Uhnkss 198.3. Overwinter forage .selection bv mule deer on seeded big sagebnisli-grass range. Journal oiWildlife Management 47: 1203-1207. . 1987. Guidelines for evaluating crop los.ses due to depredating big game. Utidi Di\ision of Wildlife Resources Publication 87-5. 42 pp. 1989. E\'iJuating production losses from mule deer deprecLition in apple orcluirds. Wildlife Societv Bulle- tin 17: 161-16.5. L 356 Great Basin Natuhallst [N'oluiiie 52 riMiDEH, J. D. 1970. Evdiiatingvvinterdeeruse of orchards in western Colorado. Transactions of the Nordi Amer- ican Wildlife Conference 35: 35^7. IGvTSMA. D. E. AND D. H. Ruscil 1979. Evaluation of deer damage in mature apple orchards. Pages 123-142 in J. R. Beck, ed., \'ertel)rate pest control tuid manage- ment materids, ASTM STP 680, American Societ\- for Testing Material. . 1980. Effects of simulated deer browsing on branches of apple trees. Journal of W'ildlile Manage- ment 44: 603-612. KuFELD. R. C, O. C. Wallmo, and C. Ff.ddema 1973. Foods of the Rockv Mountain mule deer. United States Department of Agriculture, Forest Service Research PaperRM-111.31pp, Mc'^NiNcii. J. B., M. R. Ellingwood M. J. Farcjione. AND p. PicoNE 1985. Assessing deer damage in young fruit orchards. Proceedings of the Wildlife Damage Control Conference 2; 215-223. Westwood. M. N. 1978. Temperate-zone pomolog\-.\\'. H. Freeman and Companx; San Franscisco. Calitomia. 428 pp. Received 20 April 1992 Accepted 18 September 1992 (Jrt-at Basin Naturalist 52i4i. pp. o57-.')fi3 chanc;es in riparian \'E(;etati()n along the Colorado rl\ er and rio grande, colorado \\ ancii D. SiiNclci" aiul (ianCJ. Miller" Abstract — Clianges in vegetation inchicling area oteiipied. canopx co\er, ;uk1 niatiirit)' class of cottonwoods (Poptihts spp.) within lower-clcxation zones of the (Colorado Hiverand Rio (Grande in (Colorado were monitored o\er 25- and37-\ear inten als, respectively, nsing photo-inteipretatixc nietliocLs. l"",stiniated loss oi cottonwoods along the C^olorado Ri\er was 2 lui/kni ( — 17.5% ), and remaining stands had become more open and older. ( "ottonwoods along the Rio (Grande increa.sed 1 .f) h;i/km (9.3% ) with minor canopx' cover and maturitx class changes. Area occnpied 1)\' shrnhs and ri\er channel changed little along the ("olorado Ri\er, hut declined along the Rio Grande. Loss of ha\ meadow occurred along both ri\ers. whereas dexeloped land increasi'd along the Colorado River and iarmland increased along the Rio CJrande. W'ildlile habitats alon<4 the Colorado deteriorated nuich more rapidl\ than diose along the Rio Grande tluring mcjiiitored intervals. K('i/ ircnis: riparian. Colorado, iiiroiton/. coiiomvood. Populus ,v^)^j.. wihllijc liahitaf. Ri\-eriiie .swstems in the Great Basin and southwestern United States are important hab- itats for resident and niigraton wildlife (Ander- son and Ohniart 19S(), Ilnnter et al. 1985). Two major ri\er swstems (Colorado and Rio Grande) in the southwestern United States originate within Colorado. While substantial work has been conducted to identify wildlife use and to manage riparian habitats in lower reaches of these ri\er swstems (Stexens et al. 1977, Ander- -son et al. 1978, Anderson and Oh mart 1980, 1985, Swenson and Mullins 1985), little infor- mation has been published from studies con- ducted near the headwaters of these ri\ers. The cottonwood-willow {Popidus-Salix) riparian ecosystem along Colorado's major rixers has the highest wildlife species richness and densits' in the state ( Beidleman 1 978, Fitz- gerald 1978, Hoover and Wills 1984) andisu.sed In 283 species of \ertebrate wildlife. Howe\-er, most studies ha\e centered on the South Platt(" Rixer in northeasteni Colorado (Graul and Bissell 1978). Wildlife \alues of riparian habitats along streams and rivers in the mountainous western two-thirds of (Colorado ha\ e receixed little stud\. Among ecosx'.stems in mountainous areas, cottonwood-willow rixerbottoms nsnalK' possess higli \alues for resident and migratorx' wildlife (Schnipp 1978, Thomas et al. 1979, Melton et al. 1984). Awareness of these x'alues has increascnl in recent \ears along with concern for increasing actixities in, and degradation of. these critical xxildlife zones (Windell 1980). These habitats are of .special concern in moun- tainous areas because xallevs are frequentlx narroxx' and centers of himian actixih'. Before attempting to manage riparian xegeta- tion for xxildlife, it is necessarx' to leani xx'hether these habitats are declining in ability to sustain species richness and abundance. This paper assesses recent changes and status of riparian xegetation along the Rio (irande and Colorado Rixer in southern andxx'estem C'olorado. Study a hi; a Lf)xx'er-elexation zones of the Rio Grande and (Colorado Rixer in C>olorado xxere selected for study (Fig. 1, Table 1). The Colorado Rixer and its tributaries drain about 46,196 km" of western Colorado (Ugland et al. 1984, \V)I. 2). The Colorado Rixc-r is confined to relatixelx' narroxx- xallex s until it is joined bx the (immison Rixer near CJrand function xxhere the xallex broadens xxith reduced .stream gradient. It leaxes the state xxith floxxs approximatelx 75% greater tlian at the upstream end of the studx area (Table 1). ^Colorado Dhi.sion ol Wildlifi-. .306 Cottonwood Liine, Sterling, Colorado 807.51. "Colorado Dhiskm of\\ildlif"f,.317X\'. Prospect Hoad. Fort Collins. Colorado 80.526. 357 358 Great Basin Naturalist [\ blume 52 WYOMING NEW MEXICO Fig. 1. C^olorado River and Rio Grande with iinentoried portions ( — ) and segments ( | ) in western and south centr Colorado. Tablk 1 . Characteristics of variables measured along th Colorado River and Rio Grande, Colorado. \ariable Colorado Ri\er Rio (Traude .V sampling intervixl, \t.s'' 25.0 Distance sampled, km ' 1 67.3 Sample units 21 .V hii/sample unit ST.O Sampling intensiU', % 20 Elc\ati()n, m upper 1829 lower i;372 X daily stream flow, m Vs ii])per 1005 lower 175. .5 36,8 117.4 20 163.2 2438 2286 25.3 7.0 ■'.Vi-rial plioto.s were" fn to 19.S()(C;olora. Inteipretati\e anaKses of aerial photos were contracted to the C>'olorado State Forest Senice. Vegetation t\pes, including trees (primariK tot- t(^nwoods), shmbs (tamarisk [Colorado Rixcr] and willow), hav meadows, grasslands, agricul- ture (farmland), de\"eloped (roads, towns, etc.), ri\en standing water, and umegetated (sand- bars) were delineated on acetate overlaxs using a stereoscope. Ri\er and unvegetated wei(> combined as ri\er channel. Minor vegetation tynpes {7.6dm dbh. Stands of trees were classified b\ canopy co\er as open (10-35%), intermediate' (36-55%). and clo.sed (>55%.). Changes in stands of cottonwoods from earl\' to recent photos were anah'zed using paired t tests appropriate for stratified (segment) sam- ples based on the Inpothesis that mean change was zero. Initial tests included anaKses of indi- \ idual maturitx/canopv-cover classes; howexer, sample sizes were inadecjuate to \ield meaning- ful results. Therefore, maturitx-class data for pooled canop\- cox'er classes and canop\-co\er data for pooled maturit\' classes are presented, hi addition. carK to recent changes were pre- s(Mited, wluMc cauop\' cover and maturit\' classes were [)artitioned. Changes for other cover t\p)es were anaKzed using paired t tests; ANON'A was u.sed to detect differences among segments. Mean conipaiisoiis were considered significant at P < .05. RE.su LTS ("oloiado l^iNcr Estimated loss of cottonwood stands along the Colorado River was 1.9 hii/km sample unit ( 17.5%: Table 2). Losses in the upper segment (Fig. 1), where cottonwoods initiallv averaged only 2.2 hii/km, were >90% (Table 3). Area occupied by cottonwoods was highest in seg- ment 2 where they declined 4.4 ha/km. Within downstream segments, cottonwoods axeraged 360 Great Basin Naturalist [\ olume 52 TaULK 2. Area occupied (.v lia-'kiii ) In \ egetation/Iand-iise h pe during eaiK and recent inten ids and Rio Grande, Colorado. ■ the C'olorado Ri\'er G olorado River Ri()( Grande Early Recent P Etu-K- Recent Type X SE X SE .V SE .V SE P Cottonwoods 11.2 2.1 9.2 1.7 NS 17.4 2.9 19.0 3.3 NS Shrnhs 9.5 l.S 10. 1 2.1 NS 6.5 0.9 4.9 0.7 <.05 Hav Meadow 14.7 2.9 11.2 3. 1 NS 68.6 7.0 54.5 6.3 <.03 (^nissland 3.1 O.S 4.1 1.0 NS 0.9 0.6 3. 1 1.4 <.05 Agricultiu'e .5.5 1.6 5.1 2.6 NS 0.1 0.1 13.5 5.3 <.03 De\(>loped 0.7 0.3 3.2 0.9 <.()1 0.7 0.2 1.0 0.3 NS Ri\er cliannel 9. .3 0.7 S.S O.S NS 6.2 0.4 3.9 0.3 <.01 Standing water 0.1 0.05 2.3 0.8 <.03 1.0 0.3 1.2 0.3 NS T.\BLE 3. Area occupied/segment (.v lui/kni) In cottonwoods troin earK to recent sampling intenals along the (-olorado Rixer and Rio Grande, Colorado. Segment Colorado River Early SE Recent SE Rio Grande Earlv SE Recent SE Upper Middle L NS 4.9 2.9 4.3 2.9 NS 9.3 1.3 8.2 1.8 NS about 7.5-9.3 lui/kin and ck-cliiied at more modest rates. Fith-eight percent ol the cottonwoods along the Colorado River were in the two xounger matim't)' classes (Fig. 2). The percentage of young trees ( dm-dbh) declined almost 50% (F < .01) during the 25-vear intenal. Numbers of large trees (>7.6 dm) also declined dramati- cally (/'< .02). Hectares of cottonwoods were similar among all canop\ -coxer classes during the earK sampling intenal. However, In thc^ recent sample intenal, open stands increased 11%, whereas intermediate and closed stands declined 42%r {P < .01) and 27% {P = .05), respectiveK- (Fig. 2). Hay meadow, the most abundant xegetation t\pe along the Colorado Hiver, declined 23.7%o during the sample inten-al (Table 2) with the primaiy decrca.se occurring in the lower seg- ment. (Grassland occupied 5.7% of the area during early-year .sampling but increased 31%. About 10% of the sampled area was in agricul- ture during both snnxns. Developed land and standing water were initiallx' minor but increased to 10% of the total. Oxerall, rixer chaiuiel changed little, but xariance among seg- ments was exident; the channel xxidened in the t\x'o upstream segments and narroxxed doxxni- stream. Shrubs, primanlx' tamarisk, occupied 17- 18%' of the sampled rix'erbottom and increased slightlx; primarilx' in the second segment. Shnibs occupied onlx 1.9-2.5 hii/km xxithin the upper segment, >12.4 hii/km xxithin the second and third segments, and 9.3 hii/km xxdthin the loxx'er segment. Rio (rrande Cottonxx'oods xxere moderatelx abundant x\ ithin the uppcM- segment of the Rio Grande, increasing 3.7 h;i/km (24.9%), and xx'ere most abundant xxithin the middle segment xxhere they increased2.3 lu»/km (7.7%; Table 3, Fig. 1). They xx'ere absent xxithin sexeral doxxiistream sample units, and estimated loss xxas 0.7 hii/km (13.8%). biitiallx; cottonxx'oods occupied 17. f%' of the sampled area, increasing to 18.8% bx' the sec-ond suncx' (Table 2). Small trees (<1.5 dm) represented 10.4%' of 19921 (]()I,()H\I)() HiI'Mll W \'1':CKT.\TI()\ 361 TRUNK DIAMETER (dm-dbh)r]..6 □ EARLY RECENT EARLY RECENT EARLY RECENT CANOPY COVER FitT. 2. Earlv to recent clianges/sample in niatnritx class, aiul canop\ c()\ei" of cottonwoods along the lower Colorado Hi\er, western Colorado. the coiiipo.sitiou duiing hotli saiiipk\s and increased 9.3% in occupied area (Fig. 3). Trees of intermediate size (1.5-4.0 dm) declined (F = .13) over the 36.7-year interval, giving way to the next larger (4.1-7.6 dm) maturitv class that increased 27.2% (P = .16) (Fig. 3)'. This latter group dominated among inatnritv" classes dnringboth sunevs. Large trees (>7.6 dm) rep- resented onlv 3% of the total during both sur- veys and showed little evidence of increasing in occupied area. Open stands initiallv occupied 31% of the timbered area and declined (P = .25) to 259^ I Fig. 3). In contrast, stands of intermediate clo- sure increased {F = .02) from 33 to 40%. Closed stands increased modestlv {P = .49, 9%), repre- senting 359f of the total during both sui"ve\s (Fig. 3). Hav meadows dominated among v egetation tvpes (Table 2), decreasing from 68 to 54% of tli(^ sampled area. Declines occurred primariK \\ itliin the two nj^per segments. Initiallv. grass- land was minor but it increased. primariK w ithin the upper segment. Onlv 2 of 20 samples originallv contained cropland, but the propor- tion increased to 9 of 20 samples (0.1 to 13.4%). Developed land and standing water were minor components in both earlv and recent I LU TRUNK DIAMETER (dm-dbh) EARLY RECENT EARLY RECENT EARLY RECENT CANOPY COVER Fig. 3. FarK' to recent clianges/saniple in niatnrit\' cUiss. and eanop\' co\er oi cottonwoods along the lower Hio Grande, southern Colorado. suiA'evs. Ri\er channel decreased (36.7%) throughout the studv area. .\rea occupied by shrubs was minor and estimated loss v\as 25% (Table 2). Dl.SCUSSION ('omparison of clianges along the two rivers leads to greatest concern for habitats along the (Colorado River, the much larger of the two (Table 1 ). The 25-vear interval along the C^oio- rado River was considerablv less than that for the Rio Grande, but a 17.5% decline occurred in area occupied bv trees. Development along the y'wcr increased dramaticalK and replaced manv stands of trees. Lack of natuial reproduction and/or liigli uiorialitA of voung trees v\ as indicated by a 50% reduction in stands of voung trees along the (Colorado River. Reduction of stands dominated b\ old trees, which provide primaiy habitat for ca\itv nesting wildlife, was also evident. IIov\- evcr ra])id shifts toward more open stands, which indicated excessive mortalit)- within stands, were more discouraging than changes in luaturitv structure. Thus, there were fewer and smaller stands and those remaining v\ere more 362 Great Basin Naturalist [\ bliime 52 open and occupied In' iritennediate maturih classes. Losses of cottonwoods were especially dra- matic (>90%) in the upper segment where occurrence was initiallv' low. Expansion of urhan areas, highway construction, and other de\elop- ments were responsible for much of the riparian habitat loss in a relativeK' narrow valley that initially possessed limited riparian habitat and relati\el\- rapid stream flows. Loss of trees to beaver {Castor canadensis) was noted and ma\' be important, especially in the upper segments, since many stands of cottonwoods were con- fined to streamsides by valley relief Expansion of tamarisk was evident along lower reaches of the Colorado River wdthin a broadened floodplain and slower stream flows. Increasing expansion of tamarisk severely limits opportunities for natural regeneration of cot- tonwoods and willo\\'S. Russian olive {Elaeagnus angustifolia) also is pioneering along the Colo- rado Ri\'er. This species possesses a growth form of intermediate height and, like tamarisk, may form monocultures (Knopf and Olson 1984). Stream flows along; the Colorado River haxe not shown major declines in recent decades. Large impoundments and high-elevation diver- sions, primarih- occurring during the last 50 years, ha\e altered and reduced peak flow sequences on the Colorado and Gunnison rivers. Extensive flooding occurred along the Colo- rado River in 1983-84, resulting in considerable natural reproduction of seedlings. However, infrerjuent flooding is not likely to offset the impacts of stream flow regulati(5n, streamside developments, and invasions of exotic species. Vegetation conditions and changes along the (Colorado River appear to be following the pat- tern of disrupted recruitment of native riparian phreatoplntes occurring along many western rivers (Howe and Knopf 1991). In contra.st to changes documented along the Colorado River, riparian habitats along the Rio Grande were relatively stable during the sample intenal, with an increase in area occupied by cottonwoods. However, several of the sample units within the lower segment contained few or no cottonwoods. Little evidence of seedling establishment was noted subsequent to increased stream flows during 1983-84, which raises concern for future trends. Stream flow s averaged over 10-year intenals since 1890 showed little evidence of decline at Del Norte in the west central portion of the San Luis Valley (Ugland et al. 1984, \bl. 1). However, upstream impoundments have reduced peak flows and altered patterns with stabilized increased vol- umes into late summer for irrigation. Flows downstream at Alamosa (Fig. 1) averaged about 30% of those at Del Norte, and average flows since 1930 have been about one-half of those from 1913 to 1930. Reduction in channel width was indicative of reduced and stabilized stream flows. Streamsides were dominated bv peren- nial herbaceous vegetation, which provides lim- ited opportunity for establishment of pioneering species such as cottonwoods and is indicative of moderately stable and slow stream flows through the relatively flat San Luis \ alley. Increased farmland was the most pronounced land-use change along the Rio Grande, whereas little development occurred. Shnibs (primarily willows) have not been major components along the Rio Grande in recent decades. Severe cold winters, due to high elevations (Table 1), ma\" prevent invasions of tamarisk, which has developed as a streamside monoculture at lower elevations elsewhere along riparian systems in the Southwest. Rus- sian olive was not v'et invading the inventoried Rio Grande riverbottom. Similar inventories of riparian vegetation changes and status were conducted along the South Platte and Arkansas rivers in the High Plains of eastern Colorado (Snvder and Vliller 1991 ). Deterioration of habitat along the Arkan- sas River was much greater than along western rivers in Colorado. However, conditions along the Colorado River seemed to be deteriorating more rapidly than along the South Platte River. There was also much less riparian habitat along western rivers, making that wliicli remained of greater importance. Sampling of changes between two points in time may not give an accurate assessment of long-term trends. A third inventory of these same sample units is recommended in the near future. ACKNOW LEDCMENTS T E. Owens and D. Teska of the Colorado State Forest Senice performed aerial photo inteqoretation. Assistance in sampling design and statistical analysis was provided by D. C. Bowden. W. D. Graul and G. R. Craig assisted in study design and implementation. A. E. Anderson, C. E. Braun, R. W. Hoffman, and 1992] COLOIUDO Kll'AKlAX NKCKTATIOX 363 R. C. Kiifeld proxided constnicth'e re\ie\\' of tilt' inaiiustript. This project was supported b\- Federal Aid to Wildlife Restoration Project \\'-152-R and the Nongame Checkoff Program of the C-olorado Dixision of W ildlife. LiTERATURK CiTED .\.NDKKS()N. B. \\., AND R. D. OlIMAKT lySO. Desit^Ilillg and de\eloping a predictive model and testing a re\eg- etated riparian community for southwestern birds. Pages 4.34-449 in R. M. DeGraff, technical coordina- tor. Management of western forests luid grassliuids for nongame birds. U.S. Department of Agriculture, Forest Serxice Generd Technical Report I\T-S6. . 19S5. M;uiaging riparian vegetation and wildlife along the Colorado Ri\er: SMithesis of data, predictixe models, and management. Pages 123-127 /»j R. R. Johnson. C. D. Ziebell, D. R. Patton, P F. Ffolliott, and R. H. Hanire, technical coordinators. Riparian ecosys- tems and their niiinagement. First North American Riparian Conference, U.S. Department of .Agriculture. Forest Ser\ice Generd Technical Report R.\l-12(). Anderson, B. W., R. D. Oiimakt. and J. Di.sano 1978. Revegetating the rip;uian floodplain for wildlife. Pages SlS-S'ai in R. R. Johnson, and J. F. McCormick, tech- nical coordinators. Strategies for protection and man- agement of floodplain wetlands and other ripari;ui ecosystems. U.S. Depiirtment of Agriculture, Forest Senice General Technical Report \\'-0-12. Beidleman. R. G. 1978. The cottonwood-willow riparian ecosystem us a vertebrate habitat, with particular ref- erence to birds. Pages 192-195 ;'/! \\'. D. Graul and S. J. Bissell, technical coordinators. Lowland ri\er and stream habitat in Colorado: a sviiiposium. Colorado Chapter, The Wildlife Societs- luid Colorado .Audubon Council, Greeley. Fit/,c;krald, J. P. 1978. Vertebrate associations in plant comnumities along the South Platte Rixerin northe;ist- em Colorado. Pages 73-88 in W. D. Graul and S. J. Bissell, technical coordinators. Lowland river and stream habitat in Colorado: a sxinposium. Colorado Chapter. The Wildlife Societ\' ;uk] Colorado .Audubon Council, Greeley. Getter, J. R. 1977. Procedures for inventor\ing plains cottonwoods, Morgan Count); Colorado. Colorado State Forest Service Report. 44 pp. Graul. W. D.,a\d S.J. Bissell, TECHNK.wLcoouDiN.vroas. 1978. Lowland river and stream habitat in Colorado: a s\-mposium. Colorado Chapter, The Wildlife SocieU' and (Colorado Audubon Council. Greelev. ll\HHiNt:T()N. 11. D. 1954. Manual of the pkuits of Colo- rado. Sage Books, Denver, Colorado. 666 pp. II()()\ KR. R. L., AND D. L. Wills, eds. 1984. Managing forested lands for wildlife. CJolorado Division of Wild- life and U.S. Department of Agriculture, Forest Ser- vice, Rockv M(}untain Region, Denver, Colonido. 459 pp. liowK W. H.. AND F. L. Knopf 1991. On the imminent decline of Rio Grande cottonwoods in central New Mexico. Southwestern Naturalist 36:218-224. HiNTKH W. C, B. W .Anderson, and R. D. Oiimaht 1985. Suuuuer avian communitv composition of tamarix habitats in three .southwestern desert riparian s\ stems. Pages i 28-134/;) R. R. Johnson, C. D. Ziebell, D. R. I^itton, P F Ffolliott, and R. H. Hamre, techni- cal ccjordinators. Riparian eco,svstems ;uk1 their man- agement. First North .American Riparian Conference, U.S. Department of .Agriculture, Forest Service Gen- eral Technical Report RM-120. Knoi'F F. L., and T E. Olson. 1984. Naturalization of Russian olive: implications to Rocky Mountain wildlife. Wildlife Societv- Bulletin 12:289-298. Melton, B. L., R. L. Hoover. R. L. Mooke. and D. J. Pfankucii 1984. Aquatic and riparian wildlife. Pages 261-301 in R. L. Hoover ;uul D. L. Wills, eds., .Manag- ing forested lands for wildlife. Colorado Division of Wildlife and U.S. Department of Agriculture, Forest Senice, Rock-\ Mountain Region, Denver, Colorado. Sciiiu PR D. L. 1978. The wildlife values of lowland river and stream habitat as related to other habitats in Col- orado. Pages 42-51 in W. D. Graul and S. J. Bissell, technical coordinators, Dnvland river and stream hab- itat in Colorado: a svinposiimi. Cok)rado ("hapter. The Wildlife Society and Colorado .Audubon Coimtil, Greeley. Snyder. W. D., and G. C. Miller 1991. Changes in plains cottonwoods along tlie .Arkansas and South Platte rivers — Colorado. Pnurie Naturalist 23:165-176. Stevens, L., R.T Brown, J. M. Simpson. and R. R. John- son 1977. The importance of ripari;m habitat to migrating birds. Pages 156-164 //; R. R. Johnson and D. .A. Jones, technicid coordinators, ImiTort;uice, pres- ervation, and management of riparian habitat: a ,svm- posium. U.S, Department of .Agriculture, Forest Senice General Technical Report R,M-43. ,S\\ ENSON, E. A., AND C. L. .Ml I.LINS 1985. Revegetating riparian trees in southwestern floodplains. Pages 135- 138 in R. R. Johnson, C, D. Ziebell, D. R, Patton, P F. Ffolliott, and R. H. Hamre, technical coordinators. Riparian eco.svstems and their management. First North Americiui Ripari;ui Conference. U.S. Deptirt- ment of .Agriculture, Forest Service Gener;i! Technical Report R.M-12(). Thomas, J. W., C. Maser, and J. E. Rodiek 1979. Ripar- ian zones. Pages 40-47 in J. W. Thomas, ed.. Wildlife habitats in managed forest,s — the Blue .Mountains of Oregon and Washington, U.S, Dep;irtment of .Agricul- ture, Forest Service, Agriculture Hiuidbtxjk 553. Uc;land, R. C, J. T. Steinheimer. J. L. Bl.vttner. and W. G. Kretciiman 1984. Water resourc-es data — C-oI- orado — water year 198.3. \'ol. 2. Colorado River Basin above Delores River. U.S. Geological Sunev Water- data Report CO-83-2. Uoi.AND. R. C, J. T Steiniieimer, J. L. BL.\rrNE». and R. D. Stecer 1984. Water resources data — Colo- rado— water vear 1983. \'ol 1. Missouri River Basin, Ark;uisas River Basin ;uid Rio Cirande Basin. U.S. Geo- logical Survey Water-data Report CO-S3-1. WiNDELL, J. T 1980. Colorado's water resources — uses, abuses and current status. Proceedings, Annual Meet- ing of the Colorado- Wyoming Chapter, .Americiui Fish- eries Society 15:47-57. Received 28 January 1992 Accepted 20 September 1992 Great Basin Naturalist 52(4), pp. .■3fi4-)72 RESIDENT UTAH DEER HUNTERS" PREFERENCES FOR MANAGEMENT OPTIONS Dennis D. Austin , Philip ]. Uniess , and Wes Sliields" Abstract. — A total of 3291 resident deer liunters returned questionnaires distributed at eheei90'% ), age 25—14 {529f ), and haxe more than 10 \ears of Utah dv(^v hunting experience (>6()'^). During 1989 and 1990. hunters had le.ss than 50% part)' success lor bucks on ojx'uing weekend and rel- ati\el\- low hunter satisfaction (Table 2 ). I lunter partx' success noticeabK declined betw een 1 987 and '1988 and again betAwen 1 988 and 1 989. but remained about the same between 1989 and 1990. The percentage of hunters (<20%) in the \()un«iest age class (14—24 \ears) is lower than expected. Participation b\- hunters in this age class should be highest because few people begin hunting after about age 25. These figures, consistent oxer four \ears, alone suggest possi- ])le (nture declines in the number of Utah deer hunters. However, the sharp drop in hunter participation between the third and fourth age 366 Great Basin Naturalist [Volume 52 TaBLK 2. Demographics, paitv success (%), and hunter satisfaction of Utah resident deer hunters sampled, 19S7-1990 (sample sizes in parentheses). Sex Age class" Year Male Female .V 1 2 3 4 5 6 N 1987 90.4 9.6 (863) 19.0" 31.8 23.0 14.2 8,1 4.0 (869) 198S 89.6 10.4 (444) 19.7 33.0 23.4 13.8 8.3 2.0 (458) 1 989 92.8 7.2 (925) 18.6 28.1 25.9 13.9 9.0 4.6 (936) 1990 92.7 7.3 (1429) 22.0 26.6 26.2 12.9 8.2 4.1 (1429) Mi'ans 91.4 8.6 19.8 29.9 24.6 13.7 8.4 3.7 E-xperience cl ass' Success*^ Satisf action Year 1 2 3 4 N 1987 18.7 21.3 27.2 32.8 (867) 69.3* (411) 5.3 (871) 1988 21.7 18.4 28.4 31.5 (461) 55.3 (459) 4.3 (456) 1989 22.7 15.2 25.2 36.8 (932) 48.0 (904) 4.1 (934) 1990 25.1 14.2 26.0 34.6 (1418) 47.9 (1406) 4.6 (1413) Means 22.1 17.3 26.7 33.9 55.1 4.6 '.\ge c-l^usses: 1 = 1-4-24. 2 = 2.5-04. 3 = 35-44. 4 = 4.5-54, 5 = 5.5-fi4. 6 = 65+ wars ''Experience c-lasse.s: 1 = 1-5, 2 = 6-10. 3 = 1 1-20. 4 = 21+ yeans ' I IiLiitiiig paitv success for one or more bucks on opening weekend ' Hunter satisfaction of current year's hunt in comparison to all previous deer hunts. A score of 5.0 would be expected for the average hunt. '.\ge class 16-24. Hunters aged 14 and 15 years were ineligible tor big game licenses. Hunting party success for bucks and antlerless deer on this himt. For the 19S7 season 62.516 bucks and 1168 antlerless deer were harve.sted. classes (35-44 and 45-54) is also of concern because in these age groups mam hunters" chil- dren are beginning to hunt, and parent partici- pation is a key factor in long-term sustained interest of new hunters (Decker and ConnelK' 1989). Mean age of all hunters was 36.3, 35.4, 37.0, and 36.0 \'ears for 1987-90, respecti\'elv. In a completeh- randomized survey of Utah hunters, Krannich et al. ( 1991 ) reported a mean age of 37 years and similar hunter age and sex characteristics. One probable explanation for the shaip drop in hunters in the 45-54 age class is the signifi- cant interaction between age and hunter expe- rience with hunter satisfaction (P < .04). Hunters with 20+ years of experience, who gen- erally hunted deer before the 1970s when the number of hunters was lower (Fig. 1) and hunter success rate was higher (Jense and Shields 1990), show lower satisfaction scores than younger, less-e.xperienced hunters. Mean satisfaction scores of experience classes 1-3 versus 4 (Table 2) for both years combined were 4.5 and 3.9, respecti\eK'. Similarly, mean satis- faction .scores of age classes 1-3 versus 4 were 4.5 and 3.7, respectively. Consequently, hunting moti\ ation for hunters with 20+ years of experi- ence has likely decreased because of perceived lower-qualit)' hunting. Another concern for hunter participation is noted b\ comparing the trend of hunter partic- ipation by experience classes between survey years (Table 2). No trends in hunter participa- tion were evident for hunters v\ith 1 1 or more years of experience. However, hunters v\ith 6- 10 years of experience decreased 7.1% between 1987 and 1990, while hunters with 1-5 years of experience increased 6.4%. Comparison Between Hunt T\pes Utah has had four basic t)pes of hunts since 1951, v\ith each hunt tvpe having a variable number of antlerless control permits. Either-sex hunts dominated from 1951 to 1973. with buck- only hunts dominating from 1974 to 1990, as well as before 1951. From 1985 to 1990 hunter- number- restrictive (limited-entn" and high- countn ) hunts, and from 1984 to 1989 antler-restrictive (three-point-and-better) hunts were established on some units. Buck-only hunts. — Total buck hanest averaged 63,250 per year v\ ith 8633 antlerless hanest and 181,235 hunters afield (Fig. 1). The number of unretrieved deer reported per 100 buck-only hunters in these surxevs for 1987-90 was 19.9, 21.7. 15.9. and 16.0, respectively. Using the weighted mean of 17.9, total unretrieved deer for this period was 32,441 per 1992] Hunter Opinions ()\ Dkkh Man\(;i:mknt 36- 250000 T 200000 -- 150000 -■ 100000 50000 i .A ^^ ♦ ♦ ■ - - . *v/"'' i-O^^ .'■~^V / ■ \ A-'\ \y / --■' I I I I I I I -+- I I I I I I I I I I I I I I I I I I Fig. 1. Total Iianrst ui liuck ami aiitlfrless derr and coinhiiird liiiiitrrs alifld iroiii all hutk liiiuts in L'tali, 1951-90. \"ear, and mean total annual limiting niortalit\- was 104.324. Mean hnnter sati.sfaction (19S7- 90), with 0 representing the worst hiuit and 10 the best hnnt, was 4.4. Hunting pait\" success was 45.8%. ElTHER-SEX HUNTS. — During 23 \ears of either-sex hunting, the statewide total buck har- xest axeraged 66,992, and the antlerless hanest was 39,228. Using the estimated mean for unretrieved deer (Robinette et al. 1977. Staplex 1970^ of8.0 deer per 100 hunters and the mean number of rifle liunters afield ( 153,666), a cal- culat(^d \earl\ loss of 12,293 unretrieved deer is obtained, bringing the mean total annual hunt- ing mortalit\' to 118,513. Hunter j)referenc(^ for buck-onl\' \ersus either-sex hiniting has not been addressed. ANTLER-RESTKKTIXE hunts. — Three- point-and-better, antler- rest ricti\e hunts were a\ailable on some units during 1984-89, and then discontinued. In coiiiparison with biuk- onl\ hunts. three-point-and-better limits showed a riHluction in hunters afi(4d. buck har- \est, and hunter success (Jense 1990). Howexcr. these hunts also showed a small increase in the post-season total buck to doe ratios, but a large decrease in the number of post-.season, mature bucks counted. These areas also showed a larjie decrease in the small buck (hvo-point-and-less) to doe ratio between preseason and post-season classification counts (Jense 1990). Our anaKsis confirmed the adxerse impacts of three-point-and-bett(M- hunts reported b\ fense (1990), with the highest mimber of unretriexed deer at 39.6 per 100 hunters, including 21.7 bucks. This number of bucks. luostK two-point-and-less. is compared to 4.6 bucks per l()()huut(MS on buck-ouK areas. How- e\er, hunters from antler-restrictixe areas were mod(>ratel\ satisfied, with a mean index of 4.8, and mean hunting part\ success was 55.6%. During 1989, the last \ear of three-point-and- better hunts, 40.0% [n = 931) of Utah resident hunters had hunted at least once on three-point- and-better areas, but onl\ 26.7% (n = 906) pre- ferred to continue this t\pe of hunt. Indeed, less than lialf i47.7% ) of hunters who chose to hunt these units in 1989 preferred to continue them. Facii though antler-restrictixe hunts were not successful o\er entire deer management units, selection of conscientious hunters to a\()id high iuu-etrie\ed deer losses nia\- lead to successful antler- restrictixe management. For example, at the Ea.st Canyon Resort (10,000 acres ^ in northern Utah, protecting onk 2X2 point bucks (1988-90) increased the mean 368 Great Basin Nathkalist [N'olunie 52 number of total antler tines of hai-vested bucks from 4.5 (1985-87) to 6.1 (1988-90). The per- cent of hanested l)uc-ks 2X2 or smaller decreased from 60 to 35%, while the numl)er of trophy bucks larger than 4X4 increased from 0 to 8 (unpublished data. East Canyon Resort). HUNTKR-NUMBER-RESTRICTION HUNTS. — Limited-entn' hunts have been used on some units since 1985. In comparison with buck-onlv hunts, the\ proxide higher hunter success {F < .01) and satisfaction (F < .001), with an index of 6.3, but no difference in the total munber of unretrieved deer ( 1 7.7 total deer per 100 hunters wdth 9.1 bucks and 8.6 antlerless). Hunting partv success (1987-90) was high at 68.8%. hi 1989, 22.8% of resident hunters (n = 935) had hunted deer on limited-entn' areas, and most (65.6%) indicated die fee of $22.00 was fair. While most himters {)i = 908) fa\'ored the same (37.8%) or increased (38.9%) number of limited-entn' units, hunter preferences for \ arious permit drawing and landowner hunting options were unclear. A second t\pe of hunter-number-restrictive hunt is the high-countn' hunt. This uncrowded, high-qualitv himt — but one that han-ests bucks not then available during the Octobei" rifle hunt — received positi\'e support from most (59.6%) Utah hunters. Vehicle Access to Public Lands A strong majorit)' of hunters (76.2%) indi- cated that at least some lands should be closed to vehicle access during the deer hunt to increase the qualitv of the hunting experience. However, the percentage of hunters indicating at least half of all public lands should be open to \ehicles was 74.5%. Overall, hunters indicated that a UK^m of 37.5%) of public lands should be closed to \ehicle access, vaiying by location from 28.9 to 45.4% The percentage of hunters who hunted on areas with \ (4iicle restrictions was 33.8%, while tlie pc^rcentage of hunters who indicated preference to hunt on areas with vehi- cle restrictions was 45.2%-. Using the logical assumption that the percentage of areas restricted to x'ehicles should be clo.selv propor- tional to the percentage" of hunters preferring lliem, our data .suggest the current amount of area with restricted \ehicle access is ck)se to hunter pn^erence, but that an additional 3.77f (37..5-33.8) to 1 1.4% (45.2-33.8) of public lauds should be r(\stricted. More information is needed on hunter preferences for vehicle- restricted areas in terms of size, locations, and number of areas. License Fees With the current cost of a big game hunting license set at $15.00, hunters were asked what they believed to be the fair value. Althoush Schreyer et al. (1989) reported increased license fees were opposed bv most hunters, a mean value of $15.90 was determined (/; = 1391 ) in our studv. Mo.st hunters (58.8%) indi- cated $ 15.00 was the fair \alue. Sixt) -eight hunt- ers (4.9%) indicated the fair \alue was $30.00 or more, while 58 hunters (4.1%) indicated the \alue was less tlian $10.00. It was interesting to note that costs were not related to hunter suc- cess, satisfaction, hunter choice of hunt tvpe, or whether private or public kuuls were hunted. Although license fees are strongh' and broadK' approved In- Utah hunters, few improvements in the cjualitv of the deer hunt can be made without the economic trade-off of increased hunter fees. Himter preferences for balancing potential increased fees with increased hunt cjualits need to be defined. Hunter Concerns Twent\-fi\'e categorical responses were given bv' 1% or more hunters as I'eason to quit deer hunting (Table 3). Although the list con- tains several areas of low management influ- ence, such as old atje, hiijh associated costs of hunting, and personal attitude, most areas of responses are influenced bv management deci- sions. The most connnon reasons, directlv influ- enced bv management decisions, included too main hunters, too few deer, bucks, and big bucks, private laud problems, and poor game management. Discussion Reasons to Quit Deer Hunting The proportion of mature bucks in the har- V (>st is an area of management control. It is clear most hunters prefer hane.sting large bucks infre([ut^ntlv as opposed to hanesting smaller bucks frecjuenth (Austin et al. 1990), as well as reducing some hunting opportunitv to increase the proportion ol mature bucks in the hanest (Austin and Jordan 1989, Toweill and Allen 1990). Furthermore, with tlie liunting media emphasis on tropin bucks, the pott^ntial hanest of mature bucks adds consitlerably to hunter 19921 llrx 1 KK Opinions on D\:\:h M an ackment 369 TaI51.I': 3. I'tali resident deer liuiiters' responses to the qnestion: li \ou were to (|nit deer Innitiiiij in Utah, wliat reason wonid \on list?* Nnniher of (jiiestionnaires returned: Nnrnher ot (jnestionnaires w ith no response: Nnnil)erof (|uestionnaires with "would not (juit, none Nuiuher of questionnaires with responses: Nnnilierof totd responses: 14.30 8S 4fi 129f) 2()S7 Response categories Nunil)er of responses % hunters Too nian\ hunters Too few deer Private land prol)lenis Too few hiii Ijueks Old age or phwsieal inipairnient I ligh associated costs of hunting No iU'eas to hunt or access to pnlilic lands Too few bucks Poor game management L'nethical hunters Low success or no limit on statewide lici'use sales ("hildren aged 14 and 15 \eais can hunt Deer are too small Too much \T\ use or too man\ road hunters Safet\ High costs ot licenses Personiil attitude Too few \ehicle access roads Too manv nonresident hunters Poor hunt (jualih Proclamation too long or complicati'il No either-sex or antler-restriction hunts Too manv limited-enti"\' areas Too few limited-entrs areas Too nian\' does 46 otlier categories 479 199 164 122 lOS 83 SI 79 75 72 63 4S 44 41 39 31 30 29 27 19 17 16 14 139 37.0 15.4 12.7 9.4 8.3 6.4 6.3 6.1 5.8 5.6 4.9 3.7 3.4 3.2 3.0 2.7 2.5 2.4 2.3 2.2 2.1 1.5 1.3 1.2 1.1 10.7 motixation, and Kraniiicli ci al. { 1991 ) reported that about t\vo-third.s of Ininters (66.3%) were di.ssatisiied with the si/e ol bucks. Compared with either-s(^\ huutinu;, a percentage of mature bucks hanested sliarpK decreased and has rcMuaiued at about 1 0% dunng the ])eriod ol reestablished buck-onl\- hunting (1974-90). On limited-entn hunts, the percentage of mature bucks in the hanest has exceeded 30% on most units. Not onl\- lias size of hanested bucks decreased due to decreasing mean age, but age- .specific .size has also declined (.\ustin v[ al. 1989). The aulhois beliexc a n^isonabk liigh j)er- centage (20-40%) of mature bucks in the har- \(^st is critical to successhil deer management and hunter motixation. It is clear to us that (k'creased hunting pressure on the buck [)oi)u- lation is necessaiA. The data strongK- suggest a need to establish statew ide minimum standards (or (1) age structure of the buck hanest, (2) post-season buck:doe ratios, and (3) hunter suc- cess for Inicks. Problems associated with pri\ate lands are important to hunters. These problems inchuk" poorK marked lands, trespass, pn\ ate lands cur- tailing access to public lands, and depredation. Pri\ate lands provide deer hunting for 14.8% (1990 snnex) of Utah resident hunters, and 14.7% of hunters reported owning 10 or more acres u.sed l)\ wildlife ( 1989 sunex). One possi- ble', partial solution may be to give landowniers more fle.xibilitA in management b)' allowing 370 Great Basin Naturalist [X'olunie 52 either-sex hunting on prixate lands. AcKantages include increased landowner control over deer niunbers on their lands, decreased unretrieved deer kill (Austin et al. 1990), reduced depreda- tion complaints, and improved opportunity for lianest. Furthermore, liberal hunts on private lands mav increase incentives tor landowiiers to niaik their boundaries and allow additional hunting opportunit\'. The categories of unethical liimtei's, safet\', and minimum age for hunters are closelv related to hunter education courses. Since the begin- ning of the hunter education program (1958) and the recjuired wearing of hunter-orange clf)tliing (1973), the mean number ot total Utah hunting accidents and fatalities per \ear has averaged 11.1 and 3.4, respectixelv, with about three accidents and one fatalitv occurring during the rifle hunt. Before about 195S when neither hunter education nor hunter orange was required, o\er 100 accidents and about 20 fatal- ities occurred yearK' from all hunts combined. Hunter preference to allow persons aged 14 and 15 vears to hunt big game has not been addressed. The length and complexity of the proclama- tion is a concern of hunters. Before 1979, the one-page Utah deer proclamation measured 17.5 X 22.5 inches and was printed on high- qualit)' paper, with the rules and regulations on one side and a multicolored map of Utah's deer units on the reverse. In 1990, the newsprint proclamation sheets were close to the same size (14.5 X 23.0 inches), but contained six pages. The qualit)- of the hunt in terms of the ratio of deer or bucks haivested per hunter is con- trolled by management. Although management can alter the buckidoe ratio, the total number of deer is limited by habitat, and, conxersely, hunt- ers have not been numericalK- limited. The Utah buck harvest has remained rather constant, mostly 50,000-80,000, since 1951 (Fig. 1), while the antlerless har\-esl lias shaq:)ly decreased since 1974 with the resumption of buck-onlv hunting. Total buck liimters afield from all com- bined hunts increased steadily between 1951 and 1964, decreased for three years (1964-67), slowly increased during 1967-69, but abiuptK increased between 1969 and 1973. After a second three-year period of decreasing hunters afield (1973-76), hunter numbers hax'e fluctu- ated but remained high throughout the 1970s and 198()s. CJonsetjuentlv, the himter responses of poor game management, poor hunt (|ualit\-. tlie lack of either-sex himts, and too man\- does, especiallv since changes to buck-onlv manage- ment were made beginning in 1974, have merit. Hunter crowding before about 1969 when license sales were less than 180,000 (Fig. 1) was probably a much smaller problem (Biu'eau of Government and Opinion Research 1971). Howe\er, the crowding problem of increased human population and finite resources (Leo- pold 1930) has been exacerbated because of the long-term (Leopold 1919) and more recent increasing urbanization, closures of private lands to public himting, and increased vehicle access on both prixate and public lands (\hmn 1977, Reed 1981). Our findings indicate tlie majoritx' of hunters prefer reduced hunting opportunity' for higher qualih'. When himters were asked to indicate the effect of crowding on their hunt quality', using an 1 1 -point scale where 0 means crowding greath' decreased the quality and 10 means ci'owding had no negative effect, onlv 27.8% of hunters (scale: 8,9,10) indicated crowding had little effect compared to 60.2% of hunters (scale: 0-5) who indicated a large effect (.v = 4.92). Krannich et al. (1991) reported 71% of hunters belie\ed there were too man\' hunters in their areas. Crowding effects were not signif- icantlv related to hunter age, sex, years ot expe- rience, unretrieved deer reported, or whether hunters were on private or public lands. Suipris- ingl\, the means for hunters from successful (5.04) and unsuccessful parties (4.96) were not different. These data indicate the effects of crowding are felt b\ almost all groups ecjuallw Howexer, hunters from limited-entn areas (F < .002), xvhere hunter numbers are limited, lated the effect ot croxxcling less negatixely (.t = 6.16), xx'hile hunters preferring to hunt in areas restricted from xehicles xvere more (F < .001) negatixelx- affected (.v = 4.61) than hunters pre- terrino; no restrictions (.v = 5.50). Management Options to Reduce Hunter Croxxding Sex era! options are axailable to reduce hunter crowding. Split deer hunting seasons \\ ere opposed bx' Utah hunters in recent studies (Krannich and Cundv 1989, Austin et al. 1990. Krannich et al. 1991 ). This option xx'ould likelx' increase Inmting pressure on bucks bx' increased hunter tlaxs, longer seasons, and huntinti duriuii the more xailnerable nitting 19921 Hunter Opinions on Deeh Manacement 371 period; it would therein lurtlier decrease mean age and size ot harxested hueks. A second option is to require hunters to choose either a buck or doe tag. Our suncx indicated 78.4% of resident hunters would choose a buck tag, which would reduce buck hunting pressure b\ about 21.6%. A third option is to recjuire hunters to choose and hunt onh^ one season. Since mean hunters afield for 198.S-89 combined were archen' = 26,613, rifle = 180,298, and muzzleloader = 8832, this option would reduce crowding during the rifle liunt up to approximately 20% assum- ing hunter proportions remained about the same. Hunters taxor this option: in our 1 989 and 1990 suneys, 63.8 and 64.0%, respecti\"el\-. In a 1990 completely randomized telephone sui'vev' of 14,305 deer hunters, 58.0% of Utah hunters indicated preference for this option. Krannich et al. (1991) reported a similar le\el ot support (mean score = 6.19) using a scale of 0-10. ProbabK the most effectixe option to perma- nentK reduce hunter crowding, while at the same time establishing a minimum standard for (}ualit\- in terms of hunter pressure on bucks, is tc; limit license sales of buck tags. Hunters con- sistently favor this option. In our 1990 suney 60.6% of resident hunters preferred to limit buck license sales to 150,000, with up to 35,000 antlerless tags available to unsuccessful buck tag applicants; 39.4% favored unlimited license sales. Since hunters who fa\ored limiting license sales also faxored haxing to choose sex of tag (F < .004), most hunters would favor having to choose sex of tag. Krannich et al. (1991) deter- mined most hunters (61.7%) supported choos- ing the sex of tag; and havino; vearK lianest restricted to one deer per hunter In the 1989 sunew onl\" 36.6% of hunters indicated preference to hunt e\en\'ear regard- less of future growth in hvmter numbers, while the majoritv (63.4%) selected some lexel of hunter number limitation (Austin et al. 1990). Of hunters preferring the limitation, 38.2% selected the limit at 160,000 and 25.2% selected the 200,000 limit. Prexiously in 1987, 55.8% of hunters showed preference to limit hunters to less than 200,000 (Austin and Jordan 1989). It is apparent to the authors that some restrictions are needed. We beliexc the increased buck hunting pressure beginning in 1970 (Fig. 1) has had negative effects on hunter success, satisfaction, motivation, and harxe.sted- buck size. These negative effects appear to out- weigh (lie \alues of increased wildlife manage- ment income and hunting recreation opportu- nit\. hulccd. hunter responses from these suiA ('\ s continii our \i(n\' that hunting pressure on bucks should be i-cduccd (o the pre-1970 lewl. Lite RATI' RE r:iTED Al sTi\ D. D. Ujyi. Age spixit'if antler tine counts anil c;ircass weiglits t)f huntcr-lianested mule deer from Utali cliecking stations, 19.32-1988. Division of Wild- life Resources, Salt Lake Citv, Utah. .3.5 pp. ./Vl STiN, D. D., S. D. Bunnell. .AND P. J. Uhnkss 1990. Responses of deer lumters to a checking station ipies- tif)nnaire in UtiJi. We.itern Association of Game and Fish Connnissioners Proceedings 69:208-229. .\rsTiN, D. D., .\Nl) L. JoRD.AN 1989. Responses of Utal) deer jiunters to a checking station (]uestionnaire. Great Basin Naturalist 49:1.59-166. Austin, D. D., R. A. Rioos, R J. Uhnkss. D. L. Tuhnf.h. .AND J. F. KiMB.ALL 19S9. Changes in nnile deer .size in Utali. Great Basin Naturalist 49:31-35. Bunnell, S. D.,.and D. D. .Austin 1990. Unutcropinions and questionnaires. Pages l(V-47, 87 in Deer manage- ment workshop, June, .\ugust 1990. Utah Division of Wildlife Resources, Salt Lake Citv. 94 pp. Buhe.auofGovern.ment.and Opinion Resk.muii 1971. Opinion sune\' of the people of Utali lor wildlile resources and outdoor recreation, Utah State Uni\er- sit\, Logan. 73 pp. Decker. D. J., .and N. A. Connolly 1989. Motivations for deer hunting: implications for antlerless deer har- vest as a management tool. Wildlife S(K'iet\' Bulletin 17:4.55^63. Fi.vrHEH, C. II.. AM) 1", W iloKKSTH.A, 1989. An iuiaiv.sis of the wildlife anil fish situation in the United States: 1989-2040. USDA Rock-A Mountain Forest and Riuige E.Nperiment Station General Teclinical Report R.M- 17S. 147 pp. Jense, G. 1990, Three-point strateg\ in Utah, Pages 78-88 in Deer management workshop. |nne. .\ugust 1990, Utiili Division of Wikllife Resources. Siilt L;ike Cjt\. 94 pp. |ense, G. K.,,and W. Shields 1990. Utdi big game annual report. Utah Division of Wildlife Resources Publica- tion No. 90-7. Kk vnnicii. R. S., and D. T, Ci ndy 1989. Perceptions of crowding and attitudes about a split deer hunting .season among resident and nonresident Utah deer hunters. Institute for Social Science Research on Nat- ural Resources, Utah State Universit). Logan. 29 pp. Khannk II R. S..J.S. Keitiland V. A. Riiev 1991. Utidi deer hunters" opinions about deer hunting and iilterna- tive season formats. Project Summarv Report. Institute for S(Kial Science Research on Natural Resources, Utal) State Universitv. Logan. 75 pp. Leopold, A, 1919. Wildlifers vs. game farmers: a plea for demcx-racv in sport. \C?\ Bulletin. Pages .54-fiO iu D. E. Brown and N. B. Carmony (1990). .\ldo Leopold's wilderness. Stackpole Books. Harrisburg, Pennsvlvania. 249 pp. . 1930. CJame m;uiagenient in the national forests. .\nierican Forester (July): 412—114. 372 Great Basin Naturalist [Volume 52 Mann, D. K. 1977. Land use and acquisition stud\ on wildlife ranges. Utah Division of Wildlife Resources Job Completion Report \V-65-R-D-25, Job A-S. 270 pp. McCi:llouc;ii, D. R. 1979. The George Reserx'e deer herd. Universit\ of Michigan Press, Ann Arbor. 271 pp. Reed, D. F. 19S1. Conflicts with ci\ili/.ation. Pages 509-536 ill O. C. W'allmo, ed.. Mule and black-tiiiled deer of North America. Uni\'ersit\- of Nebraska Press, Lincoln, 605 pp. Robinetpe, W. L., N. V. H.\n(xx:k, .and D. A. Jones. 1977. The Oak Creek mule deer herd in Utah. Utah Di\ision of Wildlife Resources Publication No. 77-15. 14Spp. SciiREYEK. R., R. S. Kh.wnich. .\nd D. T. Cindy 1989. Public support for wildlife resources and programs in Uttili. Wildlife Society Bulletin 17:532-538. St.\pley, H. D. 1970. Deer illegal kill and wounding loss. Final Report. Utah Di\ision of Wildlife Resotn-ces Publication W-65-R-1-A-8. 7 pp. TowElLL. D. E., and S. T Allen 1990. Results from the 15-vear policy plan questionnaire. Idaho Department of Fish and Game, Boise. 14 pp. Received 17 December 1991 Accepted 3 November 1992 Cw'eat Basin Natui;Ji.st 52i4). pp. 373— 37S LIST OF OREGON SCOL\TIDAE (COLEOPTERA) AND NOTES ON NEW RECORDS Malcolm M. Funiiss . )anies B. Jolnison . Hicliaixl L. \\estc()tt". and Torolf 1^. T<)r<^ersen' AliSTlUCr. — Listed arc 121 species of Scolvtidae Iroin Oregon. Ten species are reported from Oregon for tiie first time: HijUistcs tenuis Eiclilioff, Phlocosinits scoptiloniin scopiilontiii Swaine, Plilocosinus hofeii Blacknuui. Tn/jHxIctulnm hctulac Swtiine, Xylehonis xyl(>(>f)]th>cu\ sthtifithis ( Mannerheim) B|()L()(;Y — Monogxnous. Infests outer bark ot Salix spp., most connnonK' S. scoulcriaiia- also recorded from Ahnis spp. Ma\" reinfest stem progressi\el\' downward for sexeral genera- tions. Ca\e t\pe egg gallen; larx^ae mine shal- low 1\ under bark. Distribution and notes.— Canada: New'f.. N.S.. Que., Yukon; USA: Alas., Colo., Ida., Minn., Ut. Orecx)N: Hot Springs Camp- ground, Hart Mtn. Natl. Antelope Refuge, Lake Co., 14-MII-I99(), Salix scoulcriana, M. M. Furniss and J. B. Johnson (34 WFBM, 5 ODAC). Infesting necrotic bark lesions in a li\e stem ha\ing a deep frost crack. Diameter of infested part: 5-10 cm. Mature lar\ae present. Tn/)H>phIociis thatchcri Wood BlOLOCiY. — Monogx nous. Infests outer bark of standing. vmhealth\' or dving Popitliis tirnmloides. Ca\"e t)pe egggaller)'; lanal mines confined to outer bark. Distribution and notes.— Canada: B.C.; USA: Calif, Ida. OREGON: Hot Springs Campground. Hart Mtn. Natl. Antelope Refuge, Lake Co., 14-\III-199{), Fopulus trcnuiloklcs, M. M. Furniss and J. B. Johnson (27 WFBM, 5 ODAC). Adults attacking and walking on bark of a d\ing, 15-cm-diameter tice. PnuTi/pluihis mucroiuitiis (LeConte) BioLOC;Y. — MonogN'uous. Infests Populus trcDiitloidcs. Prefers soft, fermenting, dead bark; usualK follows primary' invasion by Tn/f)(>plil()('uspopuU Hopkins (Pett\" 1977). The gallen is narrower and the bark o\erl\ing the gallen is thicker than that of T. popnli Hopkins (and presumably T. thatclwri). One and one-half to two annual generations (Utcili), ovenvintering as lanae and adults. Eggs appear first in late Ma\. Distribution and notes.— Canada: Alta., B.C.; USA: Alas., Colo., Ida., Mont., Nev., N.M., Ut. OREGON: Hot Springs Campground. Hart Mtn. Natl, .\ntelope Refvige, Lake Co., U-\'m-l99(), Popuhis tremulokle.s, M. M. Fur- niss and J. B. John.son (9 WFBM). Infesting stem of a 26-cm-diameter tree. Jackman Park, Steens Mtn., Harney Co., 14-VIII-199(), Pop- iiJiis tronuloidt's. M. M. Furniss and J. B. John- son (14 WFBM, 10 ()D.\C). Attacking lower stem of a 25-cm-dianieter dead tree (foliage shed, l)ark moist i. Pitijophthonts scalptor l^lackman BlOLO(;V. — Presnmal)l\ pol\g\iious. Infests small branches of living pines. Distribution and notes— Canada: B.C.; USA: Calif., Ida. OREGON: 15 km \ Palmer-Junction, Union Co., Ifi-\1I1-1990, Piniis poiulerosa, M. M. Furniss and J. B. John- son (29,2c? WFBM). Infesting 1-cm-diameter freshlv faded lower branch on a li\e, merchant- able tree. Each gallerv contained only one female and one male, no eggs (jr lanae; thev appeared destined to o\en\'inter before repro- ducing. Monatiltnuii (lcnfips porosits (LeGonte) lli/hirf^ops reticuldtus Wood Hi/htr^ops nt^ipcniiis ni^ipcinii.s (Mannerheim) Uillnronps subcostuhitua sithcosUdatiis ( Vhuinerheim) Ui/lastcs 'gracilis LeGonte Hi/lastcs l(>nUis Swaine lli/lastcs macer LeCJonte Utjlastes ni'^rimis (Mannerheim) Hi/lti.stcs n/ter Swaine Ihllastcs tenuis Eichlioff H>lesinini Hijlastinm ohsainis (Mar.shani) Hylesinus califonticus (Swaine) Hi/lesiniis oregomis (Blackman) .\inipluilu/lcsiiut.s j)ini Wood Psciidohi/lcsiiuts scriceiis (Mannerlieim) Psciidohi/lcsiiuts sifclicnsis Swaine Pscuthiln/h'siiius tsiioac Swaine Doidnxinuiis hrcvicoinis LeConte Dcndntcfonus jeffrcyi Hopkins Doulroctonus pondewsac Hopkins Dendroctomis pscudotsugac Hopkins Deudroctonus nifij)emus (Kirby) Dciidrocfoiiiis valcns LeConte Phloeotribini PhltHofiihiis Iccoiitci ScheiU Phloeosinini Pldocosinus (iiitciiiKitiis Swaine Phloco.siiiits cuprcssi Hopkins Phlocosimis frdgois Sw;iine Pidocosiims hoferi Blackman Pidoeo.sinits punctatiis LeConte Phlocosimis scopidonim scoptilontni Swaine Phlocosimis secpioiae Hopkins Phlocosimis scrnitiis (LeConte) Phlocosimis laiidi/kci Swaine Hvpoborini Cluictojtldociis hctcrodoxiis (Casev) Polygraphini Cdijiholninis iittcrnwdiiis Wood Caii)hohonis piccac Wood Caqdiohorus pinicolcns Wood Cui-fdwbonis pondcrosae Swaine Cdqdiobonis sansoni Swaine Carfdioborus vandi/kci Brnck Poli/'gniphtis nifijH'nnis (Kirby) ScoLvriNAK Scolytini Scoli/tiis laricis Bkicknian Scoli/tits monlicolac Swtiine Scoh/liis limit isfriattis (Marsliam) Scoli/tu.s opticus Blackman Scoli/tits orctgoni Blackman Scolt/tiis piccae (Swaine) Scolytns pracceps LeConte Scolytits niffdosns (Miiller) Scolytns siibscabcr Le(4)nte Scolytns tsiigac (Swaine) Scolytns nuispinosus LeConte Scolytns vciitralis Le(;onte Micracini Hylocnnis hiiicllns (LeC^ontc) Cryphirgini Di>liirnim. host of Phloeosinus hofcri Black- nuin, \\ ere proxided bv Charles Johnson, USDA Forest Service, Baker, Oregon. The manuscript was rexiewed in Frank W. Merickel, Uni\ersit\ of Idaho, and Dr. Stephen L. \\ood. Brigham Young Uni\ersit\, Pro\o, Utah, who also ick'uti- tied -Y. caUfoniicus. X. xijlo^iyiplitis. and /' .v, ■scopiiloruni other than those collectetl 1)\ us. This is Uni\ersit\" of Idaho Agriculture Experi- ment Station Research Paper No. 92714. Literature Cited Bfai, ]. A., .\ND C. L. .M\ssEY 1945. Bark heetle.s and ambrosia beetles (Coleoptera: SeoKtidae) witli special reference to species occurring in North C^arolina. Duke Universit\' School of Forestr\ Bulletin 10. ITS pp. BiuciiT D. E'.. Jr. 1976. The bark beetles of Canada and .Alaska. The insects and arachnids of Canada, Part 2. Biosystematics Research Institute, Research Board, Canada Department of Agricultm-e Publication 1576: 1-241. Bkiciit n. E., JH AM) U. W. .Stahk 1973. The bark and anibro.sia beetles of California. Coleoptera: SeoKtidae and Plat\podidae. Bulletin of the California Insect Sur\i\. \ ol. 16. 169 pp. Cll,\.\liii:iu.lN, W. J. 1917. An annotated list of the .scoKtid beedes of Oregon. C>'anadian Entomologi.st 49: 321- 328, 35.3-356. ' Fha\ki.i\. J. P., AND C. T. Dyhness. 1973. Natural vegeta- tion of Oregon and Washington. USDA Forest Ser\ice Ccniral Technical Hcpoit PNW-S. Portland. Oregon. 417 pp. FiKMss, M. M., AND J. B. Johnson. 19S7. List of Idaho SeoKtidae (Coleoptera) and notes on new records. Creat Basin Naturalist 47; 37.5-382. Cast S. J.. .\I. M. Fi HNiss, J. B. Johnson, and .\I. .\. 1\ if. 1989. List of Montana SeoKtidae (Ccjleoptera) and notes on new records. Creat Basin .Naturalist 49: 3SI- 386. Petty, J. L. 1977. Bionomics of t^vo aspen bark bc-edes, Tn/popltl(H'iis popnli and Fnun/phaltis iniicroiidtiis (Coleoptera: ScoKtidac^i. Creat Basin Naturalist .37: 10.5-127. Wood S. L. 1982. The bark ;ukI ambrosia beetles of North and Central .\nierica (Coleoptera: SeoKtidae). a t;L\o- nomic monograph. Great Basin Naturalist Memoirs No. 6. 13.59 pp. Received 3 April im-I Accepted 1 October 1992 Grt-at Basin Naturalist 52(4), pp. 378^381 RIFFLE BEETLES (COLEOPTERA: ELMIDAE) OF DEATH VALLEY NATIONAL MONUMENT, CALIFORNIA William D. Sheparcr Abstract. — Three species of Elmidae occur in Death Valley National Monument: Stenelmis ccilicia is in three springs in the Ash Meadows area; MicroajUoepiisfonnicoUleiis is only in Travertine Springs; and MicroctjUocpus -similis is in several springs throughout Death Vallev and Ash Meadows. Only permanent springs support elmids. Considerable morphological variation occurs in the disjunct populations of A/, siinilis. The evolution of elmids in Death VaOey National Monument is e(juivalent to that of the local pupfish (C.ij}>rin()ilt>)i spp.). Ki'i/ iconls: Death Vallcij. In.sccta. Coleoptcrii. Ehtud(U\ (listribiitions. (Icsci-tifiration. ciohitioiL Death Valley National Monument (D\'NM) is located mostly in southeastern California, with two small extensions into southwestern Ne\ada. D\'NM includes Death VallcN' proper, its adjacent mountain ranges, and the Ash Meadows area of Nevada which surrounds Devil's Hole. Biogeographically this is a transi- tion area between the Mojave Desert and the Basin and Range Desert. Desert conditions here are the result of the drier and warmer post-Pleistocene climate and a rain-shadow effect from the Panamint Mountains, the Sierra Nevada, and the Coast Range mountains to the west. Water sources in DVNM are une.xpectedh' common. Palmer (1980) cites over 100 springs alone. Hunt (1975) has classified these springs into four tvpes based upon volume of discharge and geomoiphic origin. The Amargosa Ri\er flows (when it does!) into the southern end of Death Valley. Two permanent streams. Salt Creek and Furnace Creek, are located in the central portion of DVNM. Numerous "wells" (shallow, subsurface water sources) and "seeps" are to be found scattered throughout DVNM. These are not reliable water sources, being more or less intermittent. Wherever a water source does occur, however, it may not be \en amenable to aquatic organisms because of lethal temperatures and/or salinities. Discussions of the local hvdrolog)' can be found in Hunt ct al. (1966) and Soltz and Nai man (1978). Of the aquatic organisms occurring in DVNM, onl\- the fishes ha\e been studied extensively. Soltz and Naiman (1978) re\-iewed the past work and presented an excellent s\ni- thesis, particularly so hrCyprinoclo)i spp. (pup- fish). For aquatic insects, studies ha\e been primarilv descriptions of new species and their t\pe localities [e.g.. Chandler (1949), Usinger (1956)]; onlv one studv (Colbum 1980) directly addressed the ecolog)' of anv species. Howe\er, Deacon ( 1967, 1968) discussed insects as part of the community ecology of Saratoga Spring. During a vacation I found a single specimen of a riffle beetle in Saratoga Spring at the south end of D\'N M . That chance discoverv led me to embark on a survey of the water sources in DVNM to determine if other elmids (riffle bee- tles) occurred there, and, if so, in which sources. Methods Water Sources The water sources examined were chosen primariK- because of their accessibilitA". Those that rec^uired more than a da\s tra\el by auto and/or foot were not examined. In all, 27 water sources were examined in Death Ville)- and its enxirons, and in Ash Meadows. Death Valley water sources include: Crape\ine Spring, Scottv's Castle Spring, Mescjuite Spring, Day- light Spring, Hole-in-the-\Vall Spring, Midway Well, Sto\epipe Wells, Salt Creek, Nexares Department of Entoimilog)'. Caliloriiia Acadcinv of Sciences. Colden CJate Park, San FraTic Fair Oaks, California 9.5628. . (:.ilil()inia94ns M.iilm.' .iddress :fiS24 l.uula Sue Wav. 378 1992] Death \'ai,i.i;y Hifki,k Bkktlks 379 Springs, Texas Spring, Tra\eriine Springs, Emi- grant Spring, Naxel Spring, Tnle Spring, Badwater, Slioi-h"s Well, Eagle Borax Spring, Warm Spring, Ibex Spring, and Saratoga Spring. Ash Meadows water sources include: Indian Spring, School Spring. Dexil's Hole, Point of Hocks Spring, Jackrahhit Spring, Big Spring, and an unnamed spring. The onK' permanent water sources are large- xolume springs on the east side of Death \''alle\' and in .-Xsh Meadows, and Devils Hole. No water flows froiu Devil's Hole, hut here the surface of the ground intersects the Indrologic head of the groundwater so water is always present in the bottom of a large crevice. These permanent .sources are all connected with the Ash Meadows Groiuidwater Basin. Collections .\11 of the above water sources were exam- ined for the presence of riffle beetles. Where possible, collecting was accomplished with a standard kick-net. Howe\er, manv of the seeps and wells had such lov\' discharge and/or narrow width that collection coidd be done onlv bv manual removal of rocks and sticks for visual examination. Voucher specimens for all species collected were deposited in the author's collec- tion at California State Universitv'-Sacramento. Results ()t the 27 water sources examined, 8 were found to contain populations of elmids (Table 1 ). Steiwhiiis calicla Chandler was still resident in Devil's Hole, its t\pe localitv. However, during this survey two additional populations v\ere located in nearbv Indian Spring and F(jint of Rocks Spring. La Rivers reports unsuccess- fnllv searching springs near Devil's Hole in an attempt to locate additional populations (CJhan- dler 1949). It is not known whether these ackli- tional populations were missed or if thev are the result of colonization or transplantation. The spring nm coming from Indian Spring is vcn narrow and de(^plv incised into the desert floor, making it extremelv inconspicuous. MicwcijUocpns fonnicoklens Shepard occurred onlv at Travertine Springs (Shepard 1990). Near the spring heads (a complex of sev eral upvvellings) and for manv meters below. M.fonnicoidetis was the only elmid to be found. Further downstream, though, it co-occurs with M. siiuilis (Horn). In the lower third of the Tahi.i: 1. Tlie occurrence of rii'lle beetles (C^oleoptera: Eliiiklac) ill water .sources of Deatli\'alIe\Nation;il.VI()iiimient. Average temp. Elexation \\'ater source (C) (m) Species'' Death \alley 1 . C;rape\ine Spring 25-29 S20 2 2. Nexare's Springs - 300 2 .). Traxertine Springs 32-.36 122 2.3 4. Saratoga Spring 26-29 46 2 A.sh Meadows 5. inilian Spiing 24-30 705 1,2 6. Devils Hole 7.3.5 1 7. Point of Hocks Spring 705 1.2 S. Big Spring 681 2 Miiniajll(ici>us similis. 3 = MUnirijUoqm spring nm M. siinilis completelv replaces M. formicoidciis. Microcifllocpiissiniilis also occurs in several other springs: (Grapevine Spring. Nevare's Springs, Saratoga Spring, Indian Spring, Point of Rocks Spring, and Big Spring. All v\'ater soiu'ces inhabited bv elmids v\ere located either on the east side (jf Death X'allev or in Ash Meadows. \Mth the exception of Devil's Hole, these springs all exhibit perma- nent flow of a relativelv large volume. Most of the water sources not inhabited bv elmids are low-volume .seeps (e.g., Davlight Spring), sub- surface sources (e.g., Shortv's Well), or ])()ole{l water (e.g., Badwater). (Note added after author review: Ricliard Zack [Washington State UnivxM'sitv] has found S. calida in Skruggs Spring and Mexican Spring inAshMea(k)ws|WDS].) Discussion The major factor linking those sjiringsinliab- ited bv elmids is their association with tlu> .Ash Meackms Cyroiuidwater Basin. This large v\ater- shed nn(k)ubtedlv maintains tlu^ c-onstant fkm- recjuired bv elmids. The onlx laige-xolnnie spring not inhabited bv elmids, jackrabbit Spring, v\'as pumped diA during a local battle o\(M- water rights. .Although it mav at first seem incongruous to find riffle beetles in a desert area, one must icnieiuber that the regional desertification is a rather recent event, geologicallv and ecologi- callv speaking. During the .several Pleistocene glacial periods, and perhaps even before, the Basin and Ranee Desert was far cooler and 380 Great Basin Naturalist 1\ olunie 52 wetter. Tlie IDeatli Valley area is thought then to have had a climate much like the present-day Lake Mono area, 240 km (150 mi) to the north (Hildreth 1976). E\idence from the distribu- tions of fishes in the desert of California and Nevada and along the East Front of the Sierra Ne\ada suti^iests that many of the Pleistocene lakes ovei-flowed their basins and were con- nected by extensive river systems (Miller 1946, Hubbs and Miller 1948,' Soltz and Naiman 1978). Thus, pre-Pleistocene distributions ol aquatic organisms would ha\e been subject to changes during the Pleistocene. Ultimately, these distributions were then subjected to the influences of the warmer and drier, current interglacial period. Present distributions are, therefore, the sum of pre-Pleistocene distribu- tions. Pleistocene dispersals, and post- Pleistocene \icariant strandings. Small, isolated populations that were stranded in reliable water sources presented ideal situations for rapid evolution, given the small gene pools and lack of gene flow from other populations. These factors ha\'e been responsible for the quick proliferation of pup- fish taxa in the Death ValUn area (Solt/ and Naiman 1978). This may also account for the speciation oi M . fonuicoicleits, the dexelopment of subspecies in S. calicla, and the inter- populational variation in M. siiniUs. Stenehnis calicla had been prexiousK' reported from Ash Meadows in the form of its nominate subspecies. A second subspecies, S. c. inoapa La Rivers, occurs southeast of DVNM along the Muddy River in southeni Nevada. Each of the various populations of M. siniilis exliibits minor morphologic variations, some even in tlie aedeagus. I ha\e vacillated for a long tiuie concerning the taxonomic status of these disjunct populations. Howe\er, since the genus needs revision, and because I suspect that tlie variation is ecologically induced, I have chosen to be conservative and not assign separate taxo- nomic status to any of the populations. Perhaps some enteiprising future student will examine how constant warm temperatures influence moq3hologic expression in riffle beetles. If so, the springs of DVNM and the Basin and Range Desert would offer an excellent natural experi- ment, and the numerous populations ol .^/. siniilis in tho.se springs and spring runs would be choice stud\ material. The elmids of DVNM represent an inverte- brate analog of the alreadv well-documented evolution of pupfish of DVNM (see Soltz and Naiman 1978). Microciflloeptis fonnicoideus is similar to Ci/priiiodou diabolis in being located in only one water source and in being very distinct from and smaller than its congeners. Stenehnis calida is similar to C. salinus and C. milled in that there are two taxa (subspecies) that inhabit two separate locations along a once free-flowing water course (La Rivers 1949). Mierocijlloepus siniilis is similar to C. nevaden- sis in being widely distributed but luning iso- lated, somewhat moqihologicalK distinct populations throughout D\'NM and surround- ing areas. Elmids, like most acjuatic insects, accom- plish dispersal primariK In living adults. As the post- Pleistocene desertification proceeded, water soiux-es in the D\'NM area became smaller, fewer, and farther apart. A point even- tually had to be reached at which aerial dispersal became hazardous. Mutations reducing the abilit)' to fly would then be favored; indeed, relatively rapid fixation of these mutations in the population would be expected. It is not suipris- ing, then, that adults of all three elmids occur- ring in D\^NM are either apterous (wingless) or brachvpterous (with incompletelv developed wnigs), and subse(juentlv incapable of flying. Acknowledgments I thank the staff of Death Valley National Monument for granting permission to collect, for access to their libraiT, and for a mvTiad of helpful comments about this remarkable area. LiTER.\TURE Cited CllANDLKH 11. p. 1949. A new specie.s oi' Stviicl mis from Nevada. Pan-Pacifie Entomologist 25(3): 133-1.36. CoLHUHN, E. A. 1980. Factors influencing the distribution and abundance of the caddistlw Liiiuwphilis assiinilis. in Death Nallev. Unpul)lisiied doctoral tlissertation, Uni\('isit\ of Wisconsin. Dk.vcox. |. E. 1967. The ecolog\- of Saratoga Springs, Death N'allev National Monument. Pages 1-26 in Stud- ies on the ecology- of Saratoga Springs, Death \';illey National Monument. Final report of research accom- pli.shed under NPS Contract No. 14-l()-()4.34-1989. Nevada Southern Uni\'ersit\-, Las \egas (Universit\ ol Nevada at Las \egas). . 196S. Ecological studies of aquatic habitats in Death \'allev National Monmnent witli .special refer- ence to Saratoga Springs. Final report of research accomplished imder NPS Contract No. 14-10-0434- 19S9. Ne\ada Southeni Uniwrsib., LasWgas (Univer- sit\^ of Nevada at Las Vegas). 1992] Dkviii \'ai,i,i;y iiiKKU'; Bkktles 381 HlLDKETH. W. 1976. Death N'dlev gcoloy>. IX'atli \'alk'\ Natural I listorv Association. "2 pp. Ill UBS. C. L., .^M) H. R. MiLLKK 194S. The zoolosiical e\idence: correlation bet\veen fish distribution and Indrologic histors' in the desert basins of western United States. In: The (Jreat Basin, with emphasis on glacial and postglacial times. Bulletin of the University of Utah 38(20). Biological Series 10(7): 17-166. Ik NT, C. B. 1975. Death \alle\: geolog\. ecologw iux-heol- og^'. Uni\ersit\' ot California Press, Berkelew 2.34 pp. Ill NT, C. B., T \V. Robinson, \V. A. Bow i.ks.and A. L. Washbi KN 1966. General geolog\ of Death \alle\. C'alifoniia. H\drologic basin. United States Geological Suney Professional Pajier 494-B. 138 pp. L\ Ri\ KKS. I. 1949. A new subspecies of Stcnclinis froiu Nexada. Proc'eedings of the Entomological Societ\ of Washington 51(5): 218-224. Mii.i.KR. R. R. 1946. Correlation between fish distribution and Pleistocene hvdrologv in eastern California and southwestern Nevatki, with a map of the Pleistocene waters. Journal of Geolog\' .54: 4.3-.53. Pai.MKK. T. S. 1980. Place names of the Death \alle\ region in CiJifoniia and Nevada. Sagebmsh Press. Vlorongo X'alley, California. SO pp. ( Reissue of die 1948 printing.) SiiK.l'AKD. W. D. 1990. MicwnjUacpus formicoklcus (Col- eoptera: Elmidae), a new riffle beetle from Death N'allev National Monument, California. Entomological News 101(3): 147-1,53. Soi.i/.. D. L.. AND R. J. Nai.man 197S The natural histor\- of native fi.shes in the Death \;ille\ Svstem. Science Series No. .30. Natinal I listorv .\lu.seum of Los Angeles Coiintv, Los Angeles. 76 pp. UsiNCKH, R. L. 19.56. Aquatic Ilemiptera. Pages 182-228 in R. L. Usinger, ed.. Aquatic in.sects of Cdifornia with keys to North .Americiui genera and Califoniia sjx^cies. Universit) of Ciilifomia Press, Berkele\-. .508 pp. Received IGJulii 1991 Accepted 10 September 1992 Great Basin Naturalist 52(4), pp. 382^384 SIPHONAPTERA (FLEAS) COLLECTED FROM SMALL MAMMALS IN MONTANE SOUTHERN UTAH James R. Kucera and Glenn E. Haas" Kci/ words: flfds. SipluiiKiptcni. I'tali. ituittiuuils. Recent collections troni \arions small mam- mals of sontheni Utah have helped to elncidate the distribution of fleas (Siphonaptera) wathin the state. Of special interest were fleas of mam- mals found in forested, high-mountain areas of the southernmost part of Utah — an area of com- plex topography containing habitat varying from low desert to subalpine coniferous forests. In particular, we sampled the small mammal flea fauna of the Abajo Mountains (San Juan County), the La Sal Mountains (Grand/San Juan counties), and the Pine Valley Mountains (Washington Count)'). These ranges have been sparsel)' suneved in this respect, as evidenced by review ol the seminal work of Stark (1959). After excluding 22 records (13 SS.Ti 9 9 ) of the ubicjuitous deer mouse {\e-dActhcca iva^neri (Baker), which occurs in all counties of Utah (Beck 1955), we present and discuss the signif- icance of 42 new records of 12 species of tleas. A parallel survey of fleas found in mammal nests will be presented elsewhere (Haas and Kucera, in preparation). Mammal nomenclature is that of Hall (1981). However, designations of long-tailed \ f)l(^ subspecies should be considered tentative becau.se of the present confused state of their taxonomy. Mammals were collected with Sher- man li\{'-traps at all localities e.xcept Pines campground. Pine Vallev Mountains, and snap- traps were used at all threc^ localities in the Pine Valley Mountains and at Oowah Lake camp- ground. La Sal Mountains. An asterisk (") denotes that the host specimen (or at least one host .specimen) was deposited in the manunal collection of the Universitv of Utah Museum of Natural Histon'. Flea specimens are retained bv the authors. Hi/sfricliopsi/Ua clij)piei tnincata Holland, 1957 Pcroiui/sciis nuniiciilatiis nifiiius. San Juan Co.: Abajo Mts., Dalton Springs campground, 2560 m, 8 Septeml^er 1991; IS. Microttis loune counties. This was apparentK' oxerlooked b\ Stark ( 1959: 196), who stated, ^This flea appears confined to the northern half of the state." Egoscue (1988) reported collecting one male specimen from a pika at Johnson Resenoir, Sevier Count)', in south central Utah. The dis- tribution map of Haddow et al. (1983: Map 76) indicates a locality record in that same region of Utah. Our records are the first for southeastern Utah. Mcgabothris abantis is usuall)' found on \arious species o^ Microtus. EuDiolpianus cuinolpi aiiicricanus (Hubbard. 1950) Tamias sp. San Juan Co.: Abajo Mts., Dalton Springs campground, 2560 m, 8 September 1991^2 9 9. These specimens seem closer to E. c. aiuer- icaniis than to E. c. eutnolpi recorded by Beck (1955, then in the genus Monopsijllus) . Several of the t)pe specimens were collected in San Juan Count)- (Hubbard 1950). Johnson (1961) indicates that intergradation between E. c. antcri- caiius and E. c. cuuiolpi occurs in the conutx. In snmmaiy, the significant findings among 64 collection records of 13 species of fleas are as foHows: the first records south of (he (Colorado Rix'er in southeastcin I'tali (or Hi/strichopsi/lla (lippici tniiicata, Corrodopsi/lla c. cunaia. Pcr- oDiijscopsijlla svlcnis, and Megaboihris abantis; and the first in Washington Count); southwest- ern Utah, for //. occidentalis si/lvaticns, Rhacl- inopst/lla s. scctilis, P. selenis, luid Opi.soda.sys kccni. Acknowledgments We thank H. Egoscue and C. Pritchett for their review of the manuscript; and E. Rickart, Universitv of Utah Museum of Natural History, for assistance in identifsing some Pcroint/scus specimens. Literature Cited Bkck D E. 1955. DistrihutioiiaLstiiclies i)f' parasitic arthro- pods in Utah, determined as actual luid potential \ec- tors of Rock\' Mountain spotted fever and plague, with notes on vector-host relationships. Brighani Young Universitx' Science Bulletin. Biologic;il Series 1 (D. Ca.mpos. E. a.. .\sd H. E. Stark. 1979. A revaluation [sic] of the HijstrichopsijUa occidentalis group, with descrip- tion of a new subspecies (Siphonaptera: Hvstrichop.s\llidae). Journal of Medical Entomology 1.5: 431-444'. EcoscLF,, H. E. 1966. New ami additional host-flea associ- ations and distributional records of fleas from Utah. Great Basin Natrn-alist 26: 71-75. . 19SS. Noteworthv flea records from Utah, Ne\ada, and Oregon. Great Basin Naturalist 48: 530-532. . 19S9. A new species of the Genus Tmnhclhi (Siphonaptera: Ceratoph\llidae). Bulletin of the Southern Ctilifornia Academv of Sciences SS: 131-134. R\AS, G. E., R. P. Mahtin. M'. Swickard. and B. E. Miller 1973. Siphonaptera-mammiJ relationships in northcentral New Me>dc(). [ournal of Medical Ento- niolog\- 10: 281-289. Haddow. ]., R. Traub, and M. Rothschild 1983. Dis- tribution of ceratoph\ Hid fleas and notes on their hosts. Pages 42-163 in R. TraTib, .M. Rothschild, ;uid J. F. Haddow, The Rothschild collection of fleas — the Ceratoplnllidae; ke\s to die genera and host relation- ships with notes on their e\olution, zoogeograplu' and medical importance. 288 pp. [Privateh published.] Rall, E. R. 1981. The mammalsof North America. 2nded. 2 \olunies. John W'ilev & Sons, Inc.. Ne\v York. 1181 pp. Hubbard, G. A. 1947. Fleas of Western Nordi America. Iowa State Gollege Press. 533 pp. . 1950. A pictorial rexiew of the North .Americiui chipmunk fleas. Entoniologic;il News 60: 25.3-261. Johnson. P. T. 1961. .\ re\ision of the species oi Mono- pstjlhis Kolenati in North America (Siphonaptera. Geratophvllidae). Technical Bulletin No. 1227, Agri- cultural ReseLUX'h Sel^ice, U.S. Depiutment of .Agiicul- tiue. 69 pp. JOHNSON P. T. AND R. Tr.M R 1954. Rexision of die flea genus Pcroini/.scop.si/lla. Smithsonian Miscellaneous Gollections. \'ol. 123. No. 4. 68 pp. S( HAFKR, T. S. 1991. Mammdsof die Abajo Mountains, an isolated nioimtain range in San Juan Gountw southeast- em Utah. Occasional Papers No. 137. The Museum. Texas Tech University, Lubbock. .Stark. II. E. 19.59. The Siphonaptera of Utali. U.S. Dep;ut- ment of Health, Education and \\'elfare. Gommunica- ble Di.sease Genter, Atlanta, CJeorgia. 2.39 pp. Thton \'. J., AND D. M. .\llrkd 1951. New distribution records of Utah Siphonaptera with the description of a new species of Mc^ai-throfilosstis Jordan and Rofli- .schild, 1915. Great Basin Naturalist 11: 10.5-114. Received 22 May 1992 .\ccej)ted 2 November 1992 (iix'iit Basin Naturalist 52(4 K pp. 385-^386 NOTES OX SPIDER (THERIDIIDAE. SALTICIDAE) PRED ATIOX OF THE 1IAR\ESTER AXT, POGOXOMYRMEX SALIXUS OLSEX (HYMENOPTERA: FORMICIDAE: MYRMICIXAE), AND A POSSIBLE PARASITOID FLY (CIILOROPIDAE) William II. Clark' and Paul Iv Bl( Kl'i/ uorcls: Poiiononnnnex saliniis. luirvcstcrdiil'-^. Eunopis t( .\\sti(iis. spider predators. Inccrtclla. parasite. Spiders are known predators of ants. Pres- sure exerted bv consistent spider predation can alter the behaxior of ant colonies (MacKax 1982) and ma\' be a selectixe pressure contrib- utintj; to the seed-hanesting behaxior of P(><^oiii)iiii/n)wx (MacKax' and MacKax* 1984). We obsened the spider Eim/opis fontiosa Banks (Araneae: Tlieridiidae) capture and transport xx'orkers of tlie lianester ant [Pogotiomijrmex salinus Olsen [Hxiiienoptera: Fonnjcidae, MxTmicinae]) in soutlieasteni Idalio. .Xdditional obserx'ations rexealed a crab spider of the genus Xijsticus prexing on P. salimis and the presence of a clikjropid fix' (IiicerteUa) that max- liaxe been parasitizing the moribund prev subdued bx' the spider. Study Sitk One collection site is located along Road T-2() (Butte Count); T4N, R31E, S6)"on the Idaho National Enxironmental Research Park (INERP) in the cold desert of southeastern Idaho. The second set of observations xvas made on the INERP (Clark Countx; T7N, R31E, S34. along Highxx'ax' 28). X'oucher specimens of all species have been deposited at the Oniia ]. Smith Museum of Natural Histon, Albertson College of Idaho, Caldxxell, Idali()'83605 USA (CIDA). Results .am) Discussion On 3 July 1988, 1020 h. at the Butt(> ( :()uutx collection .site xx'e collected a single indixidual of Eiirijopis fontiosa Banks (Araneae: TluMidiitkic) that x\as earrxing a worker of Pofj^otionu/niicx sdliiuis Olsen (Hxnienoptera: Formicidae, Mxrmicinae) across a large area of basalt rock. The ants xxere actixelx' foraging in the area. The air temperature (shaded) xvas 31 C] and the soil siu-face (in the sun) xvas 39.5 C. No other spiders of this species xvere encountered. Prev capture xx'as not obsened. On 31 August 1991 at 1725 li at tlic Clark Counts- site xxe obsened a ciab spider of the genus Xi/sticiis pre\ing on P. sal inns about 20 cm from the ant nest entrance. The ants xx'ere still actixelx- foraging at this time. One spider xxas riding on the ant in the shelter of an isolated clump of Indian ricegrass [On/zopsis lii/ttie- nuides) at the edge of the ant moimd. Tlu^ ant xvas initiallv vew actixe. xxalking around an old grass stem, xxhile the spider made periodic attacks on the ant. As time progres.scd, inxolim- tan- spasms in th(^ ant increased. The spider xx'as generallx- oriented toxx'ard the posterior of the ant, biting it at the base of the petiole. Some- times the spider xxas peipendicular to the ant. holding on to the ant xxith onlx' its mandibles. .\fter fixe minutes the ant fell onto its side and moxements sloxxcd. .\t 1740 h onlx its antennae xx'ere mox-ing slightlx, and a minute later the spider moxed the ant under a small stick. Tx\-o small flies approached die ant and one flexx- onto its head. Occasional moxements (jerks) of the ants legs xxere obsened at 1751 h. At this time x\-e collected the spider, the ant, and one of the Hies (WHO #9170). The fly is a female Incertelki I Diptera: Chloropidae) and may represent an undescribed species. Broxvn and Feener (1991) Orma J. Smith Must- uiii of Natural I liston . Alhert.son College of Ulalio, Caldwell. I(cf)li(ili(s paraponerae selecti\eK' parasitizing 1 1 loril )uncl workers oi Para- ponera clavata. It may be that these InceiicUa flies are seeking a similar host and opportunis- tically exploiting the spider prey. The flies were not obsened to interact with li\'ing, active ants. At 1740 h we noticed a second spider, E. formosa, on tlu^ same ant mound. This spider oriented uphill on the side ot the mound, facing the ant nest entrance. At 1742 h an ant walked over and slightK* past the spider, apparentlv failing to recognize the predators presence. The spider remained motionless as the ant passed, then spim around and mounted the ants gaster. The spider released the ant and moved to face it. The ant began convxdsing at this time, while the spider sat 1 cm away from the ant (facing awav from the ant). Bv 1745 h no motion was obsened in the ant and at 1746 h the spider climbed onto the ant. The ant was on its side with the spider on top facing the gaster. A fly similar to those mentioned aboxe moved onto the head of the ant. At 1747 h the spider was draggincr the ant across the moimd usingr a web sling, as previouslv described b\' Porter and Eastmond ( 1982) for the spider E. coki in south- eastern Idaho. The spider dragged the ant to the edge of the mound and into the grass clump mentioned earlier. Several other worker ants were obsened strung up in the grass clumps. At this point we collected the spider (WIIC #9171 ). The spider genus Eunjopis is known to pre\' on ants (Le\i 1954, Carico 1978), including har- vester ants of the genus Pogonomijnnex in North America (MacKay 1982, Porter and East- mond 1982). MacKay (1982) has reported PJ. ralifoniira previngonP. rii^osiis in southern California. Prey of E. fonnosa lias not pre\"iousl\" been reported (Levi 1954), nor has the spider been reported from the INERP (Levi 1954, Allred 1969). Levi (1954) gives the distribution of the species over most of kkdio except for the south- western comer, so its presence here was ex- pected. Allred ( 1 969) reported a related species, Eiinjopissvriptipcs Banks, from the southeastern border of INERP during July. Ponono»ii/n)iex salirms is tlie dominant .seed-luuvesting ant on tlie INERP, occurring in almost all of its plant commu- nities (Blom et d'. 1991). Porter and Ea.stmond ( 1982) found Ejinjop- sis coki Lc\i to be a comuion preckitor of Po'^oinxntjnncx ouijhcci {^P. .saliniis) in south- eastern Idaho during July and August. These small gra\" spiders capture ants on their mounds and drag them awa\' bv a web sling attached to the ant and to the tip of the spider's abdomen. Ell rif apsis fonnosa is found from central Cali- fornia north to British Columbia and east to Wyoming (Levi 1954). E. foiDiosa mav also be an important predator of P. salinus at this site and of Pooonomijnnex species in the western United States. The relatively greater precision and speed with wliich Eunjopsis subdued and transported the P. salinus prev suggests an established predator-pre\' relationship. ACKNOWLE ])G M E NTS This work was conducted under the IN EL Radioecologx' and Ecology' Programs sponsored bv the Office of Health and Environmental Research, and the Division of Waste Products through the Fuel Reprocessing and Waste Man- agement Division, United States Department of Energ)'. O. D. Markham, T D. Revnolds, and y. B. Johnson have provided assistance. ]. McCaffrev and H. W. Levi provided spider determinations. C. W. Sabrosky identified the Inceriella specimen and B. V. Brovvm assisted. This paper is published as Idaho Agriculture Experiment Station Paper No. 91767. Literature Cited Ai.i.HED. D. M. 1969. Spiders of the National Reactor Test- ing Station. Great Basin Naturdist 29: 10.5-108. Bl.OM R E., \V. H. ClARK A\D J. B. JOHNSON 1991. Golonv densities ot the seed haivesting ant P()g(>n()ini/nuex.sali)Uis (Hviiienoptera: Formicidae) in se\en plant communities on the Idalio National Engi- neering Laboraton'. [onrnal of the Idaho Acadenn of Science 27: 2(S-36. Bhown. B. v., and D. H. Fekner. Jr 1991. Behavior and host location cues of Apocctyiuilns paraponcrac (Dip- tera: Phoridae), a parasitoid of the giant tropical ant, Vdraponcra clavata ( Ihnienoptera: Formicidae). Biotropica 23: 182-187. Carico, J. E. 1978. Predaton- behavior in Eiin/opis fuiicris (Hentz) {Ar;mea: Theridiidael and the evohitionan significance of web reduction. Svmposium of the Zoo- logical Societx of London 42: .51-.58. I.l'A I II. \V. 1954. Spiders of the genus Eiinfopsis from North and Central America. American Museum Novitates 1666: 1-lS. MacKav, W. P 1982. The effect of predation t)f western widow spiders (Araneae: Theiidiidae) on hanesterants ( Hymenoptera: Formicidae). Oecologia53: 406—111. M \( Kay. W. R, an d E. E. Mu:Kay 1984. \\'h\' do haivester ants store .seeds in their nests? Sociobiologv 9: 31—47. PoRTKR, S. D., AND D. A. Eastmond, 1982. Eiinjopis coki (Tlieridiidae), a spider that prevs on Po^oiicmi/nm'x ants. Jounial oi .Arachnologv 10: 27.5-277. Received 6 Fchntan/ 1992 Accepted 10 September 1992 THE GREAT BASIN NATURAUST INDEX VOLUME 52 - 1992 BRIGHAM YOUNG UNIVERSITY Great Basin Naturalist 52(4), 1992, pp. 38.S-391 INDEX Volume 52—1992 Author Index Acker, Steven A., 284 Agenbroad, Larrv D., 59 Allred, Kelly W., '41 Anderson, Stanley H., 139, 253 Arnow, Lois A., 95 Arnovv, Ted, 95 Austin, Dennis D., 352, 364 Beck, Reldon R, 300 Bernatas, Susan, 335 Blackburn, Wilbert H., 237 Block, William M., 328 Bloni, Paul E., 385 Boe, Edward, 290 Bonhani, Charles D., 174 Burge, Howard L., 216 Callahan, J. R., 262 Clark, William H., 385 CcMiistock, fonathan R, 195 Cooke, Lynn A., 288 Cottrell, Thomas R.. 174 Cronquist, Arthur, 75 Cushing. C. E!., 11 Davis, Russell, 262 Deleray, Mark A., 344 Ehleringer, James R., 95, 195 Elias, Scott A.,59 Evans, R. R, 29 Flinders, Jerran T., 25 Furniss, Malcolm M., 373 Caines, W L., 1 1 Gill, Ayesha, E., 155 Hems, Glenn E., 382 Hcill, Linnea S., 328 Haws, B. A., 160 HoN'ingh, Peter, 278 Hubert, Wayne A., 253 Jehl, Joseph R., Jr., 328 Johansen, Jeffrev R., 131 John.son, James B., 373 Johnston, N. Paul, 25 Ka\, Charles E., 290 Kaya, C^iilvin M., 344 Kitchen, Stanlev G., 53 Knapp, Paul A.,' 149 Kucera, James R., 382 Kucera, Thomas E., 122 Kudo, J.. 29 Launchbaugh, Karen L., 321 Leidy, Robert A., 68 Lindzey, Frederick C. 232 Miirks, Jeffrey Shaw, 166 McArthur, E. Durant, 1 McNult^', Ining R., 95 Mead, Jim I., 59 Meyer, Susan E., 53 Miller, Gary C, 357 Morrison, Michael L., 328 Moselev, Robert K., 335 Munay Leigh W., 300 Negus, Norman C, 95 Nielsou, M.W., 160 Norling, Bradley S., 253 Palmquist, Debra E., 313 Pendleton, Rosemaiv L., 293 Pickering, Russell, 309 Pieper, Rex D., 300 Quinnev, Dana L., 269 Rasmussen, G. Allen, 185 Roberson, Jay A., 25 Roche, Ben F, Jr., 185 Roche, Cindv Talbott, 185 Rumble, Mark A., 139 Rushforth, Samuel R., 131 Saab, \'ictoria Aiui, 166 Scoppettone, G. Gan; 216 Sexille, Robert S., 3()9 Sheelev, Douglas C;., 226 Shepard, \\'illiaiu D., 378 Shields. \\'es, 3(>4 Shiozawa, D. K., 29 Simanton, J. Roger, 237 Slaugh, Bartel f., 25 Smith, Bruce N., 93 Smith. LorcMi M., 226 Smith. S, D.. 11 Snvder, Warren D., 357 Stanton, Nanc\' L., 309 Swiecki, Steven R.. 288 388 19921 Index 389 Taxlor. Daniel M., 179 Thomas, Diane M., 309 Torgersen, Torolf R., 373 Trost, Chiu-lesII.. 179 Tuttle, Peter L.. 216 Tyser, Robin W'., 189 Uresk, Daniel W'., 35 Unless. Philip J.. 321. 352. 364 \an Sickle, Walter D.. 232 V'icken. Robert K.. )r., 145 \'(K)rhees, Marmierite E.. 35 Wagstaff. Fred J.. 293 Wansi, Tchouiissi, 300 Welch, Bruce L., 293 VVeltz, Mark A., 237 Westcott, Richard L., 373 Wester, Da\id B., 226 Williams, R. N., 29 Wood. Stephen L., 78, 89 Woodward, S. R., 29 Yeiirslev, Kurtis H., 131 Yen.sen, Eric, 155, 269 Young, James A., 245, 313 Keyword Index age-growth, 216 alien flora, 189 alpine \asculiu- flora, 335 aiiiilwsis f'actoi-. 174 fecal, 3(X) dietan-, 269 microhistological . 300 Anas acuta, 226 annual grass, 245 Aplanusiclla, 160 apple trees, 352 aquatic habitat, 278 arid lands, 149 Aristida. 41 Artemisia nova, 313 fiidcntata. 174 tiidcntiita tridcntata. 2S4 tridcntata wyoinin^ensis. 284 arthropods, 59 avifauna, 278 bark beetles, 78 beardtongue, 53 Beaver Dam Creek, [Utali], 131 behaxior, 25 foraging, 293 benthos, 11 big sagebrush, 284 biochemical differentiation, 155 biogeography, 262 biomtiss, 313 leaf. 237 birds, 278 migrating, 179 black sagebrush, 313 h()d\" condition, 226 size, 216 browse, 293 bumblebees, 145 bunchgrass, 284 burrow- stucture, 288 California, 41, 122 Death \'alle\', 378 Mono Lake,' 328 caribou, 321 caves, 59 Ccntaiirea lirt^ata ssp. scjuarrosa, 185 cerxid, 321 checking stations, 364 ch romatographv, 1 74 chukar, 25 reai'ing, 25 Cicadellidae, 160 cold desert, 11, 195 Coleoptera, 11,78,89,378 colonization, 328 colonizing .species, 245 Colorado, 174, 357 Colorado Plateau, 59, 195 Columbian Shaip-tailed Grouse, 166 competitixe release, 68 Cottonwood, 357 cutthroat trout, 29 Cijnomys lencunts, 288 Death Vallev, [California], 378 deer, 321 damage exaluation, 352 management, 364 mule, 122, 290, 352, 364 white-tciiled, 290 depredation, 352 desert, 278 soil formation, 313 streams, 131 desertification, 378 diatoms, 131 dietarx anaKsis, 269 Diptera, 11 dispersal, 262 distribution(s), 160, 378 390 Great Basin Naturalist [y^ oluiiie oz distuihance, 253 DNA sequencing. 29 drought response, 237 Eiiiwria, 309 eleetivities. 68 electrophoresis, 155 elk. 321 Elniidae, 37(S Ephenieroi")tera, 1 1 Ethco.stoina /i/gn///i, 6S Eun/opsis fonnosa , 385 e\'olution, 378 (actor anaKsis. 174 faunal list, 373 fecal analysis, 300 fecundit\', 216 Felix concolor, 232 fish, .344 (leas, 382 flora alien, 189 alpine \ascular. 335 riUT, 335 floristics, 41 llowei' colors, 145 food habits, 216, 269 foraging beha\ior, 293 forest management, 139 fruit trees, 352 functional groups. 1 1 ghost towns. 149 Glacier Park, [Montana], 189 Grand Ganvon. [Arizona], 59 grassland, 95 grayling, 344 grcizing, 35, 245 Great Basin, 195, 278 De.sei-t, 149 green ash, 35 ground squirrels, 155, 269 Grits ct/nadciisis. 253 habitat a(|uatic. 278 ck'scriptions, 139 selection, 139, 253 summer h. characteristics, 166 use, 179,216 hanester ants. 385 hibemaculum, 288 hosts, 160 hummingbirds, 145 hunter opinions, 364 Idaho, 166, 269, 335 Kane Lake Girque, 335 Pioneer Mountains, 335 Idaho ground scjuirrel, 155 imprinting, 25 hurHrlla. 385 induced dormancN, 53 Insecta, 378 Intermountain West, 95 interspecific h\'bridi/.ation, 290 inyentoiy, 357 iiTigation resenoirs, 179 islands, 328 Kane Lake Girque, [Idaho], 335 lake. 344 land bridge, 328 leaf area index, 237 leaf biomass, 237 leaflioppers. 160 Lcpiis califonticiis, 300 life histon', 216 long-term site degradation. 284 mammals. 382 management, 166 deer, 364 forest, 139 medusahead, 245 Mclca^ris oallopaio, 139 MeiTiam's Wild Turke\s, 139 microhabitat use, 68 microhistological anaKsis, 300 Microius. 262 iiioiitdiiiis. 328 migrating birds, 179 migration, 122, 344 Miiiiiiliis. 145 MiXipa coiiarcd. 216 Moapa dace, 216 Mono Lake, [Galifornia], 328 Montana Glacier Park, 189 moiphological specializations, 68 Muddy Ri\er, Ne\ada. 216 mudflats, 179 mule deer, 122, 290, 352, 364 mushroom, 321 nncophagw 321 Nebraska Platte Ri\er, 253 nest, 288 Ne\ada, 216 Muddy River, 216 new genus, 160 new species, 160 niche breailth, 68 nomenclature, 75. 78. 89 Northern Pintails. 226 nutrients. 293 nutrition. 321 oak-majile. 95 Ocloccilciis hcinioiius. 122.290, 293 viriiiiiidnii.s. 290 Odonata. 1 1 19921 Index 391 OiicDrJii/iirJiits. 29 orchards. 352 Oregon. 2podidae. 78. 89 Pleeoptera. 1 1 Pleistocene, 262 Pooonomijnnex saliniis, 385 |)ollinator preferences, 145 poK merase chain reaction, 29 poKsporocystic coccidia. 309 Populus spp., 357 predictive models, 226 piexalence, 309 pr()dncti\it\". 11 propa- James R. Ehleringer, Lois A. Arnow, Ted Arnow, Irving R. McNulty, and Norman C. Negus 95 Influences of sex and weather on migration of mule deer in California Thomas E. Kucera 122 Diatom flora of Beaver Dam Creek, Washington County, Utah, USA Kurtis H. Yearsley, Samuel R. Rushforth, and Jeffrey R. Johansen 131 Stratification of habitats for identifying habitat selection by Merriams Turkeys Mark A. Rumble and Stanley H. Anderson 139 Pollinator preferences for yellow, orange, and red flowers of Mituuhis vcrbenaccus and M. cardinalis Robert K. Vickery, Jr. 145 Soil loosening process following the abandonment of two arid western Nevada townsites Paul A. Knapp 149 Biochemical differentiation in the Idaho ground squirrel, Spermophilus bntuneus (Rodentia: Scuridae) Ayesha E. Gill and Eric Yensen 155 New genus, Aplanusiella, and two new species of leattioppers from southwestern United States (Homoptera: Cicadellidae: Deltocephalinae) M. W. Nielson and B. A. Haws 160 1992] Index 393 Summer hal)itat use hy Columbian Sharp-tailed Crouso in western Idaho \ictoria Ann Saab and Jeffrey Shaw Marks 166 Notes Characteristics of" sites occupied by subspecies o( Artr7nisia triclrntata in the Piceance Basin, Colorado Thomas K. Cottrell and Charles D. Bonham 174 Use of lakes and reservoirs b\ miuratini; shorebirds in Idaho Daniel M. Taylor and Charles H. Trost 179 Dispersal ot scjuarrose knapweed (Centaurea vir<:,ata ssp. squarrosa) capitula by sheep on rangeland in Juab County, Utah Cindy Talbott Roche, Ben F. Roche, Jr., and G. Allen Rasmussen 185 Vegetation associated with two alien plant species in a fescue grassland in Glacier National Park, Montana Robin W. Tyser 189 No. 3 — September 1992 Articles Plant adaptation in the Great Basin and Colorado Plateau Jonathan P. Comstock and James R. Ehleringer 195 Life history, abundance, and distribution of Moapa dace [Moapa coriacea) G. Gar\- Scoppettone, Howard L. Burge, and Peter L. Tuttle 216 Condition models for wintering Northern Pintails in the Southern High Plains Loren M. Smith, Douglas G. Sheeley, and David B. Wester 226 Evaluation of road track surveys for cougars (Felis concolor) Walter D. Van Sickle and Frederick G. Lindzey 232 Leaf area ratios for selected rangeland plant species Mark A. Weltz, Wilbert H. Blackburn, and J. Roger Simanton 237 Ecology and management of medusahead {Taeniathcrum caput -medusae ssp. asperum [Simk.] Melderis) James A. Young 245 Roost sites used by Sandhill Crane staging along the Platte River, Nebraska Bradley S. Norling, Stanley H. Anderson, and Wayne A. Hubert 253 Post-Pleistocene dispersal in the Mexican vole (Microtus tnexicanus): an example of an apparent trend in the distribution of southwestern mammals Russell Davis and J. R. Callahan 262 Can Townsend's ground squirrels survive on a diet of exotic annuals? Eric Yensen and Dana L. Quinney 269 Notes Avifauna of central Tule Valley, western Bonneville Basin Peter Hovingh 278 Wildfire and soil organic carbon in sagebrush-bunchgrass vegetation Steven A. Acker 284 Structure of a white-tailed prairie dog burrow Lynn A. Cooke and Steven R. Swiecki 288 Hybrids of white-tailed and mule deer in western Wyoming Charles E. Ka\- and Edward Boe 290 No. 4 — December 1992 Articles Winter nutrient content and deer use of gaml)el oak twigs in north central Utah Rosemary L. Pendleton, Fred J. Wagstaff, and Bruce L. Welch 293 Botanical content of black-tailed jackrabbit diets on semidesert rangeland Tchouassi Wansi, Rex D. Pieper, Reldon F. Beck, and Leigh W. Murray 300 Species oiEimeria from the thirteen-lined ground squirrel, Spennophihis thdecemlineatus , from Wyoming . . Robert S. Seville, Diane M. Thomas, Russell Pickering, and Nancy L. Stanton 309 394 Great Basin Naturalist [Volume 52 Plant age/size distributions in black sagebrush {Aiicinisia nova): etlt-cts on communit\ structure James A. Young and Debra E. PalnKjuist 313 Mushroom consumption (mycophagy) by North American cervids Karen L. Launchbaugh and Philip J. Urness 321 Terrestrial vertebrates of the Mono Lake islands, California Michael L. Morrison, William M. Block, Joseph R. Jehl, Jr., and Linnea S. Hall 328 Vascular flora of Kane Lake Ciniue, Pioneer Mountains, Idaho Robert K. Moseley and Susan Bernatas 335 Lakeward and downstream movements of age-0 arctic grayling (rhymallus arcticus) originating between a lake and a waterfall Mark A. Deleray and Calvin M. Kaya 344 Effects of browsing by mule deer on tree growth and fruit production in juvenile orchards Dennis D. Austin and Philip J. Urness 352 Changes in riparian vegetation along the Colorado River and Rio Crande, Colorado Warren D. Snyder and Gary C. Miller 357 Resident Utah deer hunters' preferences for management options Dennis D. Austin, Philip J. Urness, and Wes Shields 364 List of Oregon Scolytidae (Coleoptera) and notes on new records Malcolm M. Furniss, James B. Johnson, Richard L. Westcott, andTorolfR. Torgersen 373 Rittle beetles (Coleoptera: Elmidae) of Death Vallev National Monument, California William D. Shepard 378 Notes Siphonaptera (fleas) collected from small mammals in montane southern Utah James R. Kucera and Clenn E. Haas 382 Notes on spider (Theridiidae, Salticidae) predation of the harvester ant, Po^onomynncx salinus Olsen (Hvmenoptera: Formicidae: Mvrmicinae), and a possible parasitoid fly (Chloropidae) ' William H. Clark and Paul E. Blom 385 Index to Volume 52 387 INFORMATION FOR AUTHORS The Great Basin Naturalist welcomes previously unpublished manuscripts pertaining to the biologi- cal natural history of western North America. Pref- erence will be given to concise manuscripts of up to 12,0()() words. 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FINAL CHECK: • Cover letter explains any duplication of infor- mation and provides phone number(s) • 3 copies of the manuscript and WordPerfect disk • Conformity with instructions • Photocopies of illustrations (ISSN 0017-3614) GREAT BASIN NATURALIST Vol 52 no 4 December 1992 CONTENTS Articles Winter nutrient content and deer use of gambel oak twigs in north central Utah. . . . Rosemary L. Pendleton, Fred J. Wagstaff, and Bruce L. Welch 293 Botanical content of black-tailed jackrabbit diets on semidesert rangeland . . . Tchouassi Wansi, Rex D. Pieper, Reldon F. Beck, and Leigh W Murray 300 Species of Eimeria from the thirteen-lined ground squirrel, Spermophilus tri- decemlineatus, from Wyoming Robert S. Seville, Diane M. Thomas, Russell Pickering, and Nancy L. Stanton 309 Plant age/size distributions in black sagebrush {Artemisia nova): effects on community structure James A. Young and Debra E. Palmquist 313 Mushroom consumption (mycophag)') by North American cervids Karen L. Launchbaugh and Philip J. Urness 321 Terrestrial vertebrates of the Mono Lake islands, California Michael L. Morrison, William M. Block, Joseph R. Jehl, Jr., and Linnea S. Hall 328 Vascular flora of Kane Lake Cirque, Pioneer Mountains, Idaho Robert K. Moseley and Susan Bernatas 335 Lakeward and downstream movements of age-0 arctic grayling {Thymallus arc- ticus) originating between a lake and a waterfall Mark A. Deleray and Calvin M. Kaya 344 Effects of browsing by mule deer on tree growth and fruit production in juve- nile orchards Dennis D. Austin and Philip J. Urness 352 Changes in riparian vegetation along the Colorado River and Rio Grande, Colorado Warren D. Snyder and Gary C. Miller 357 Resident Utah deer hunters' preferences for management options Dennis D. Austin, Philip J. Urness, and Wes Shields 364 List of Oregon Scolytidae (Coleoptera) and notes on new records Malcolm M. Furniss, James B. Johnson, Richard L. Westcott, and Torolf R. Torgersen 373 Riffle beetles (Coleoptera: Elmidae) of Death Valley National Monument, Cali- fornia William D Shepard 378 Notes Siphonaptera (fleas) collected from small mammals in montane southern Utah James R. Kucera and Glenn E. Haas 382 Notes on spider (Theridiidae, Salticidae) predation of the harvester ant, Pogonomyrmex salinus Olsen (Hymenoptera: Formicidae: Myrmicinae), and a possible parasitoid fly (Chloropidae) William H. Clark and Paul E. Blom 385 Index to Volume 52 387